difference between /clearallqueuedabilities and /clearabilityqueue ?

[gm9]

Have been working on the UI a bit today, redoing all the curing code. Since it was requested I'll add the functionality to automatically cancel pending spellcasts so the cures go right through. I thought I should also clear queued abilities just to make sure they don't kick in before the cure.

Searching for the right command to use for that I found these two

/clearallqueuedabilities
/clearabilityqueue

Anybody know the difference between them? From testing they seem to behave identical, but maybe I'm missing something. Thanks.