Smooth transitions between ISDs should not be preferred

[nigelmegitt]

The note beneath the [associate region] algorithm states:

Where an implementation is able to detect significant similarity between two adjacent synchronic document instances, DOCinterN DOCinterN−1, then it is preferred that the implementation make the transition between presenting the two instances as smooth as possible ...

The use of the term "preferred" is territory-specific and not culturally accepted globally, so it should either be removed or scoped to the places where it is true. For example in the US smooth scrolling is preferred, whereas in the UK jump scrolling is preferred, and those preferences are strong active preferences.

I propose to change the wording to: "..., then the implementation may apply processing to make the transition between presenting the two instances as smooth as possible..." to remove the preference.

I suspect @mikedo could be particularly interested in this, based on my recollection of previous conversations.

[skynavga]

This note comes from TTML1 without change, so this issue should be moved to TTML1 repo, and an entry added to #358.

[nigelmegitt]

Done, this is w3c/ttml1/#304. It seems pointless to close this issue and add something to another issue, so leaving this as is.

[skynavga]

Closed, as this is now a duplicate of #358.