I hate it when you pass someone a brand new tank, or a warrior, then he leaves or lags out of the game before he enters the unit. The unit becomes "Blue Tank" or "Red Tank" or whatever team he's on...just AI pilot in it and nobody has control over it.
The only thing you can do is to get a sniper rifle and kill the pilot in it. Of course this isn't possible with all units. Like scavs, walkers, assault tanks etc. So you have to wait for another joiner to assume control over them.
Is there a way to make these units transferred to the commander, or other teammates, in case this happens? Maybe that might be a problem if the commander has tons of units and all the F keys assigned....hm....where do they go then? :}
Talked about this in the private beta at langth and the code rewrite required would not have been worth the effort. We all would have loved the feature but in the end if would have taken too long a time.