In most scenarios, you should be able to keep up with these kinds of pulls. The biggest issue honestly comes when the tank isn't mitigating whatsoever and they expect you to just heal through, which you can do... but it's annoying.

I personally find very little value in completing a dungeon in 15 minutes instead of 17, but I also don't think it's too difficult to do wall-to-wall pulls if everyone's just playing their job right.

You can always ask the tank to slow down a bit if it's really too tough for you.