It is something I sometimes want to do, but find hard to justify. First of all, when I played, it was competitively and I found it hard to get fun out of just playing casually. In fact, I have quite addictive behaviour so I usually ended up addicted to games I played competitively. (CS:S, L4D(2) and COD2/4).

I know myself well enough to know that I can not play "in moderation" and would tend towards the competitive aspect. (Single player games never really entertained me that much)