More to the point it doesn't help you. But let me ask you this: if you intend for the AI to do the capping and repairing, what do you want to do? Just the fighting part? Maybe it should also build the base buildings and the units, or mop up some pioneers or bikes that you consider a nuisance. CoH however is about micromanaging your units and employing them to their full effect. Capping is a big part of CoH because it helps you get an advantage and deprives the enemy of resources. I realize in the heat of battle you might forget to repair your vehicle or capture an important point, but thats the difference between a good player and a bad player. A good player can do this things simultaneously and therefore wins, that's how it should be. If you automize(is that a word?) certain parts of the game you water down the difference between a good player and a bad player.
If you're going to make Pioneers auto-repair, it's only fair to make all repair units auto-repair. And even then, it's still not a very good idea in this kind of game... What if your units are busy fighting the enemy, and a nearby friendly vehicle takes damage? They will move to repair it, stopping them from attacking, and making themselves more vulnerable to fire...
Oh come on, what's the use of that? You want your infantry to just run blindly into the fray and be annihilated trying to cap the point? You can already do that by shift+clicking by the way. But I'm sorry, if it is too much of a hassle to repair your vehicles and recapture points then maybe this game isn't for you and you should rather have go at Civ IV (which I consider to be excellent).
No, no, you're all missing my point. As i stated in my first post in this topic (quoted above), i don't like too much automation. Sure, it makes sense with some things, like your units automatically attacking, but if the game is going to play itself, you might as well just watch a film! That's why we like videogames, isn't it? The interactivity?
How long have you been playing Company Of Heroes? Engineers and Pioneers are actually capable of attacking...