[Imp]

Think it does but not enough to offset the gains, pure guess but think works as follows from least to most gain.
Takes part
Fired at
Fires damages unit or kills a man
Kills a unit.

So assume if damaged as above losing a man hurts a bit but its gained the first 2 bonuses anyway so if it can do a bit of damage to it will still gain.
Pure speculation on my part, gaining experience to 70 should be pretty quick & to elite again moderatly fast but after that it should go to a crawl which is in my view were the problem is. Once they reach 100 & boosted morale absolutly deadly, 130 becomes plain silly Rambo style. Not only are they marginaly more accurate they have kevlar vests & spot other units with ease, the only thing you have to watch is ammo as have loads of shots. Of course the game is not setup for them as I dont think you would ever see a 100 exp unit in a regular battle.