Suggestion - Role swapping in instance

[Amelia_Pond_Behemoth]

I would like this feature. But the problem is, you'd still be down one person, which might screw with people who are in queue. Say for instance.

Queue in as a DPS for Halatalii HM.

You're in the dungeon. Tank decides to dip. You then commence a role swap. The tank who was in queue for that spot might end up getting screwed due to the role swap happening. So you'd need to wait on a DPS to fill the slot in that you originally had when you first got into the instance.

What's the worst that could happen? The tank doubles the amount of time he's in the queue? Zero times two is still zero.