I would never want this sort of mutator to be played across the board - I would just like to see an inidvidual server, or possibly an individual map, be made for team-tanking....".
I agree with that sentiment, but a few ppl worry when suggestions like this arise- there's really no need as it would be popular with a few only a players, on the odd server at the most.
I think a variable position swap and enter/exit delay would be good for CA maps with 1-3 tanks, obviously to discourage ppl trying to run off with one of the few tanks available- but also to create a tank that needs to be fully crewed to reach full potential ( driver or gunner swapping to hull mg, whilst enjoyable is a bit too easy and reduces need for that 3rd man)
Also if the enter exit delay is introduced, the squad leader can't instantly jump out and spray AT infantry- again it's fun but hardly fair. It would be better if the tank's own infantry worked to protect it (assuming it crossed their minds to do so of course...)
This kinda mut could be used by some servers to encourage TT- i'm not gonna say it should cos it's a touchy subject, but i will say this.
The guy who sprints to the only panther and says that's mine- get a p4 or stug is not really being fair and helping the team IMO. If he is that good he should be able to manage a lesser tank on his own anyway.
So agreeing with wolf- were a mutator like this to be used on an predominately tank map, it should be flexable to allow the delays to be altererd, or even eliminated for certain tanks- it seems the right thing to do and should keep most ppl happy.