I think the time out isn't a bad idea in terms of separating the cats so that the situation doesn't escalate, but I don't think it will do much good in terms of teaching the cat a lesson. It's been my experience that cats don't really understand the cause and effect process that humans do--and generally dogs can also follow it I think--so when the cat was in time out I wonder whether or not she realized it was because she misbehaved. I employ the time out tactic when my cats are playing and things start to get a little rough, I like for them to play but only if it's playing the second one of them looks unhappy I separate them because I don't want either one to develop aggressive behavior, but I don't think the cats put 2 and 2 together because it does not stop them from rough housing a few minutes later.
