I know this wasn't the intent of your question as it was WDW-focused, but the key with TSM is to go to the other coast. I have never even come close to walking on TSM at WDW. Usually even the FP line has a bit of a wait. On the other hand, last October, during morning magic hours (or whatever they call it on the other coast) at California Adventure, we walked on twice in a row. Literally, not a single other person waiting around us. We could have gone even more than the two times we rode, but my arm muscles were already in spasm from riding twice in a row with no break in between! Pulling that trigger and scoring so many points is hard work!