Update assumption

_rules/audio-as-media-alternative-afb423.md

@@ -41,7 +41,7 @@ The label (from expectation 2) is [visible][] and [included in the accessibility
 
 ## Assumptions
 
-This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/audio-text-alternative-e7aa44.md

@@ -44,7 +44,7 @@ For each test target, the [outcome](#outcome) of at least one of the following r
 
 ## Assumptions
 
-This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/audio-transcript-2eb176.md

@@ -33,7 +33,7 @@ The auditory information of each test target is available through a text transcr
 
 ## Assumptions
 
-This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/form-control-label-descriptive-cc0f0a.md

@@ -54,7 +54,7 @@ Each target element describes the purpose of the associated form field element.
 ## Assumptions
 
 - This rule assumes that the [label](https://www.w3.org/TR/WCAG21/#dfn-labels) is intended for sighted users, and that hiding a visible label from assistive technologies, is a failure of [Success Criterion 4.1.2 Name, Role, Value](https://www.w3.org/TR/WCAG21/#name-role-value), but not of [Success Criterion 2.4.6 Headings and Labels](https://www.w3.org/TR/WCAG21/#headings-and-labels).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/heading-descriptive-b49b2e.md

@@ -35,7 +35,7 @@ Each target element describes the topic or purpose of its [section of the conten
 
 ## Assumptions
 
-This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/html-page-title-descriptive-c4a8a4.md

@@ -40,7 +40,7 @@ The target element describes the topic or purpose of the overall content of the
 
 ## Assumptions
 
-This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/iframe-identical-name-equivalent-purpose-4b1c6c.md

@@ -40,7 +40,7 @@ The `iframe` elements in each set of target elements embed the [same resource][]
 ## Assumptions
 
 - This rule assumes that, within the context of the test subject, the description provided by the [accessible name][] of an `iframe` can only accurately describe one resource (notably, homonyms alone are not used as `iframe` names). Thus, if two or more `iframe` elements have the same [accessible name][] but embed different resources, at least one of them does not describe its purpose.
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/image-filename-as-accessible-name-9eb3f6.md

@@ -29,7 +29,7 @@ Each test target has an [accessible name][] that serves an equivalent purpose to
 
 ## Assumptions
 
-This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/links-identical-name-equivalent-purpose-b20e66.md

@@ -44,7 +44,7 @@ When followed, the links in each set of target elements resolve to the [same res
 
 - This rule assumes that the purpose of the links with identical [accessible names][accessible name] would not be ambiguous to users in general when seen in context on the web page, which is the exception mentioned in [Success Criterion 2.4.9 Link Purpose (Link Only)][sc249]. If the links are ambiguous to users in general, users of assistive technologies are not at a disadvantage when viewing the links out of context, e.g. on a list of links in a screen reader, which makes it more of a general user experience concern than an accessibility issue.
 - This rule assumes that, within the context of the test subject, the description provided by the [accessible name][] of a link can only accurately describe one resource (notably, homonyms alone are not used as link names). Thus, if two or more links have the same [accessible name][] but resolve to different resources, at least one of them does not describe its purpose.
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-alternative-for-auditory-eac66b.md

@@ -33,7 +33,7 @@ For each test target, the [outcome](#outcome) of at least one of the following r
 ## Assumptions
 
 - This rule assumes that the video element is used to play a video (for example, not only used to display an image), and that there is a mechanism to start the video.
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-alternative-for-visual-c5a4ea.md

@@ -39,7 +39,7 @@ For each test target, the [outcome](#outcome) of at least one of the following r
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-as-media-alternative-ab4d13.md

@@ -33,7 +33,7 @@ Each test target is labeled as a video alternative for text on the page. This la
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-audio-description-1ea59c.md

@@ -28,7 +28,7 @@ The visual information of each test target is available through its audio, or th
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-description-track-f196ce.md

@@ -30,7 +30,7 @@ _Note_: Multiple description `track` elements may be useful for different langua
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-only-alternative-for-visual-c3232f.md

@@ -43,7 +43,7 @@ For each test target, the [outcome](#outcome) of at least one of the following r
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-only-as-media-alternative-fd26cf.md

@@ -37,7 +37,7 @@ The label (from expectation 2) is [visible][] and [included in the accessibility
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-only-audio-track-d7ba54.md

@@ -27,7 +27,7 @@ The visual information of each test target is available through an audio track.
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-only-description-track-ac7dc6.md

@@ -30,7 +30,7 @@ _Note_: Multiple description `track` elements may be useful for different langua
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-only-transcript-ee13b5.md

@@ -34,7 +34,7 @@ The visual information of each test target is available through a text transcrip
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-strict-alternative-for-visual-1ec09b.md

@@ -35,7 +35,7 @@ For each test target, the [outcome](#outcome) of at least one of the following r
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support
 

_rules/video-transcript-1a02b0.md

@@ -39,7 +39,7 @@ A text transcript containing all the visual and auditory information of the test
 ## Assumptions
 
 - This rule assumes that a mechanism is available to start the video and that the video element is not simply used to display the [poster](https://www.w3.org/TR/html5/semantics-embedded-content.html#element-attrdef-video-poster).
-- This rule assumes that the language of the page can be correctly determined, either programmatically or by analyzing the content.
+- This rule assumes that the language of each test target can be correctly determined (either programmatically or by analyzing the content), and sufficiently understood.
 
 ## Accessibility Support