Blizzard's stance has always been, if you can do it with a macro or addon, its okay.
And in the past they have changed the API, specifically to break functionality in certain addons.

As long as the addon API allows it.
I cannot see anyone having an issue with it.
If they change the API, so this functionality is broken... and you find a way around it, that could lead to repercussions.

That said, its your accounts... so make your own decision.