TouchEvent sub-pixel precision

Hi,
The latest CSSOM View editors draft proposes a modification to MouseEvent
(and others) to enable fractional co-ordinates:
http://dev.w3.org/csswg/cssom-view/#extensions-to-the-mouseevent-interface.
 This is most valuable in high-dpi scenarios (i.e. essentially all
tablets/phones and now many laptops) to provide more precise co-ordinates
to applications, so that they can result in maximum smoothness for slowly
moving elements.

I've suggested (https://www.w3.org/Bugs/Public/show_bug.cgi?id=24095) that
if they're going to modify MouseEvent for this, they should modify Touch at
the same time.  Without this, for example, it's impossible to implement
scrolling in JavaScript that is as smooth as browser native scrolling.  I
don't think there's any good reason for Touch to be 2nd class to mouse in
this regard.

Thoughts?
  Rick