You guys rock.
But seriously, though, I think this can be pretty useful. For example, if a user continues spamming a thread, rather than continuous infractions (leading to an auto ban that may or may not affect them), we can sorta give them a "second chance" by simply banning them from the thread for a set amount of time (I'm thinking... maybe 3 days as an initial ban?). Seeing as it's a thread ban rather than a site ban, we can start off with a higher time limit since it affects them less severely.