I feel like good management of your pios/engineers is part of the skillset of the game - if the repair failed, you didn't control the units properly. The micro requirements aren't so high that we have to make it easier with more auto-behaviours. It's good to have things to improve on. Use S to make sure the vehicle has stopped and isn't pushing the repair units out of the way - happens a lot with damaged engine vehicles.
This topic is basically about that units should do as ordered the first time. It shouldn't be necessary to give the same order 2 or more times.
And I think you're confusing micro with lack of unit control.
For a game to have the best link between victory and players' abilities, micromanagement should reward players who react best to the designed and intended mechanisms in the game.
I'm pretty sure that disrupted repairing is not an intended feature and thus micro management to offset it is really a sidetrack. It does not contribute to the ideal link between best player and victory. It is more kind of 'noise' in that equation.
Just as tanks that bump into corners of a branch and change heading. Or mortars that don't fire beacuse one of its crew is milling around and can't find a proper prepared position. It is also 'noise' because it hits a player in random.
And pressing 'S' does not help btw. This problem occurs AFTER the vehicle has been stopped. It is caused by the relocation when other units pass. Or if a target comes into range, plus a number of other reasons.
I think it will be hard to deal with this glitch because it is so situational and has roots in how unit AI works in general.
That's why I suggested auto repair as a simple solution. The code was in COH1, so I suppose it would be possible.
But nm if there is another solution that is more agreeable.
As for the function that lets pios/engies follow a moving vehicle and keep repairing it tokenly, I would actually prefer to see that removed. It will increase micro, but will purify the repair situation: repair only takes place when pios/engies are stopped.
So if there's any fairness in this forum, the micro manaiacs amongst you should at least applaude the latter suggestion.