You mean for mixed vehicle convoy driving? I did some tests on that too and made some videos yesterday but I was unable to upload them so far and currently I'm dl the ACR expansion. I still need to do some testing in form of what impact rank has in convoy driving there are still some things which are not really clear. It should have some impact the same as waypoint behavior does.
In any case the driving is good in general. The flaw IMO consists in what I've described above. Fix the group leader default behaviour in boarding the last convoy vehicle and convoys will improve. When the group leader boards the lead convoy vehicle it takes the convoy just the time until all AI have boarded their vehicles and they are rolling. In the 1st video I made it took the AI nearly 3 minutes or even more to get unstuck. In the second video the convoy rolled out as soon as every AI was on board on their vehicles. No insane AI driving.