Collision Detection, a little over zealous?

[Aruberikku]

Yea, I noticed it sometimes too.
I've collided when trying to fly in tight formation, while I could have sworn there was still a tiny bit of room lol. But yea, lag can be an important factor here.

And especially some ground units don't have a good "collision border", I've tried flying under a bridge once that wouldn't let me. Most do though.