Out of supply should effect tanks more

[BenWH]

In my previous games, I gave the AI a big advantage, and it managed to research things much quicker than I can (not sure how research works, even with max labs I am always left well behind). In both games it's tanks were about level 17 when mine were level 5. This threw up a situation that seemed wrong to me. I would cut off his tanks, reduce their effectiveness to red, and leave them without supply, then attack them with mine. I would STILL loose 10 tanks for 0. This does not seem to be right. Either stationary, demoralised tanks should surrender, or I need to have the ability to park my tanks behind them and shoot them up the rear. Either way, I would expect better results than this!