The first thread (useless panties) degraded rather quickly and belongs in the S.P.O.T as a result. The second thread (hidden panties) could only be viewed as a retread of the same. That the first thread belongs in the S.P.O.T is unquestionable. Sure it's a theory thread (a rather silly one though), but in it's current state (innuendo and spam) the S.P.O.T was the only place for it. However the second thread is really the one called to question, but since it is another take on a thread that degraded to the point of being sent to the S.P.O.T it's understandable why it would be sent there as well. It's like sending the Chaco thread to the S.P.O.T only for someone to create "Chaco Thread - Part 2", so I don't disagree with DT's decision.
Whether or not they are considered "proper theory threads" is irrelevant.