[cssom-view] Is there a need for a plural form of document.caretPositionFromPoint()?

In bug 19753[1] I mentioned to add a plural version of
document.caretPositionFromPoint() besides the one for
document.elementFromPoint(),
so you can get the caret positions of all elements at a specific point.
Another idea was to add an element-specific function
caretPositionFromPoint()[2], which would take coordinates relative to the
given element.

Now I was asked for possible use cases for this function, though
unfortunately I can't remember if I had a good one.
One was related to having two overlapping text fields or areas used to
enable auto-completion like it's done for the Firebug Command Line. Though
there you don't necessarily need the position of the overlapped field.

So I'm asking around if somebody sees a need for such a function.

Sebastian

[1] https://www.w3.org/Bugs/Public/show_bug.cgi?id=19753
[2] http://lists.w3.org/Archives/Public/www-style/2012Oct/0702.html