Before the new training with bonuses... in the old game... I think a friendly cost you the same condition as hard training and you earned the same increase in skills. That may have swayed in favour of training once the new training system came in with bonuses/different levels. However, you could very well be onto something now with the new penalties for disproportionately higher attributes. Once upon a time I would have conducted tests to experiment, but those days are long gone as I have ever decreasing motivation for this game... particularly for training which is nothing but a chore.