I think Cthulhu is trying to say:
If there is a collision it might just end up on one person's computer. Which means if it is on your FE then you would get stopped suddenly but the person you collided with would keep going causing a while list of whines and confusion as well.
Now given the speed that gv's move in by comparison to aircraft this may be less of an issue than mid-airs are but still an issue none-the-less.
I however agree that it would be nice if you could not drive through other gv's and it is very unrealistic but limited on options as well.
Pretty much. If I understand the code as it is, collisions with stationary objects are handled by your PC and the server only, whereas collisions between players is a much more complex affair between both PC's and the server.
Let me ellaborate. Say you hit a sheep. The location of that sheep is defined by the map which is local to your PC (I believe). Everybody sees that sheep in exactly the same location on their PC, so colliding with it is handled purely by your PC (and the results of the collision relayed to the server).
Your position relative to another moving player is, due to network issues, well,
a matter of opinion. Provided you have minimal network delays, then both PC's (and hence both players) can pretty much agree on where they both are. However, as network delays and vehicle speeds increase, we start to see more of the weird and annoying collision behavior that we're all familiar with in aircraft.
dkff49 is right in that the much lower speeds would make it much less of an issue for GV's, but I suspect that HTC would wind up using the same collision code that it uses for aircraft.
Frankly you're right waystin2. It's silly to be able to drive thru nme GV's. But I suspect that HTC has the code set up that way because something very squirrelly happens when they turn on collisions.