Switching jobs while in a duty

[CazzT]

I see, does make sense if you look at it that way.

However, since you have experience with WoW, how often did you encounter situations in PUG content wherein players are asked to change to a more meta spec?

Never outside of Heroic/Mythic raiding. In LFD/LFR, I encountered people queuing as tank or healer and then not filling that role more times than I can count. It's hard to say which was more common between the two roles doing this, but it was frequent.