Merge pull request #800 from w3c/concurrent-input-mechanisms

Concurrent input mechanisms

understanding/21/concurrent-input-mechanisms.html

@@ -10,28 +10,27 @@ <h1>Understanding Concurrent Input Mechanisms</h1>
 		<section id="intent">
 			<h2>Intent</h2>
 			<section id="benefits">
-        <p>When interacting with web content, users may employ a variety of input mechanisms (such as keyboard and keyboard-like interfaces, or pointer devices such as a mouse, stylus or touchscreen). Certain tasks and interactions will be easier for a user to accomplish with a particular input device.
-        Users may switch between input mechanisms at any point during their interaction. Input mechanisms may dynamically be added or removed. Even if a device has a primary/preferred input mechanism (for instance,
-        the touchscreen on mobile phones and tablets), the user may instead employ alternative input mechanisms (such as a paired mouse or external keyboard in the case of mobile phones and tablets).</p>
-        <p>Content must therefore be "input agnostic": not make assumptions about which input mechanism is the primary/preferred one, and not limit the user's interaction to any particular input mechanism, unless the restriction is essential, required to ensure the security of the content, or respect user settings.</p>
+        <p>Users may employ a variety of input mechanisms when interacting with web content. These may be a combination of mechanisms such as a keyboard or keyboard-like interfaces and pointer devices like a mouse, stylus or touchscreen.</p>
+        <p>Even though a device may have a primary or preferred input mechanism, the user may choose to apply alternative mechanisms. For example, a primary mechanism is the touchscreen on mobile phones and tablets, while a paired mouse or external keyboard may be an alternative.</p>
+        <p>Dynamically adding, removing or switching a particular input mechanism should be doable at any point by a user if certain tasks and interactions are easier to accomplish that way. Content must therefore not limit the user's interaction to any particular input mechanism unless the restriction is essential, or is required to ensure the security of the content or to respect user settings.</p>
+        <p>Note: A touch-typing web application, which teaches users how to touch-type on a keyboard and/or measures their proficiency and speed, would be an example of an essential limitation to a particular input mechanism. </p>
         <h3>Benefits</h3>
 				<ul>
-					<li>Users are able to interact with web content with whichever input mechanism is available to them.</li>
-          <li>Users are able to add/remove input mechanisms.</li>
-          <li>Users can switch between input mechanisms when they desire or the circumstances demand it.</li>
+					<li>Users can interact with web content with whichever input mechanism is preferred and available to them.</li>
+          <li>Users may switch between input mechanisms when they desire or the circumstances require it.</li>
+          <li>Users are allowed to add and remove input mechanisms at any point, where supported by the operating system.</li>
 				</ul>
 			</section>
 		</section>
 		<section id="examples">
 			<h2>Examples</h2>
-				<ul>
-					<li>Even though content is being viewed on a mobile phone with a touchscreen, a user with a mobility impairment is able to pair a mouse and keyboard (or equivalent input devices) with the phone and operate the content - the content does not assume that the touchscreen is the only input modality the user will want to employ.</li>
-          <li>On a touch-enabled laptop, users are still able to interact with content using their trackpad and keyboard.</li>
-          <li>A user starts interacting with a page using a keyboard on their computer, and they attach a secondary touch-enabled monitor. Content can be operated using this newly added input mechanism, and does not assume that the first input mechanism it detected (the keyboard) is the only one in use.</li>
-					<li>A speech input user navigates content using voice commands which translate to simulated keyboard commands; however, when simultaneously talking with a colleague, the user switches speech recognition off and uses the mouse instead.</li>
-					<li>A touch-typing web application, which teaches users how to touch-type on a keyboard and/or measures their proficiency and speed, would be an example of an <em>essential</em> limitation to a particular input mechanism. In this case, the application would not be required to allow the user to switch to an alternative input mechanism.</li>
-					<li>[TO DO] Security exception example...</li>
-				</ul>
+      <ul>
+        <li>A user with mobility impairment pairs a mouse and keyboard to her mobile phone with a touchscreen. The phone can thereafter be operated by those input devices and the content does not accept the touchscreen as the only input mechanism.</li>
+        <li>On a touch-enabled laptop with coarse precision, people who have difficulty activating a small target because of hand tremors, limited dexterity or other reasons are still able to interact with content using their keyboard and trackpad.</li>
+        <li>A user starts interacting with a page using a desktop keyboard, and then attaches a secondary touch-enabled monitor. Content can be operated using this newly added input mechanism and does not assume that the keyboard, the first input mechanism it detected, is the only one in use.</li>
+        <li>A speech input user navigates content using voice commands which translate to simulated keyboard commands. When talking with a colleague, however, the user switches speech recognition off and uses the mouse instead.</li>
+
+      </ul>
 		</section>
 		<section id="resources">
 			<h2>Resources</h2>