I've only played CT once, and my enthusiasm dropped to 2 after the game, and was at 3 for my next game, which I lost by 9 points. Had i had the normal enthusiasm, I probably would have won the last game, not to mention the game for which I played CT (although i did hold my opponent to 53 points while i scored 102). If you have a pretty good team, i think you don't have to worry about playing CT as the consequences can be harmful later on. My enthusiasm just returned to 5 sometime last week. It stayed below 5 for about 1.5 weeks though. Not sure if it was a certain number of matches or time passed. Hope this helps.
Graham