No, not sex (at least not that I know of). What I mean is that Judgers will often get more done than Perceivers. I've been experimenting recently; going with the flow - moving without a plan - and thinking on my feet. And I've recognised that structure increases efficiency in accomplishment all the time. It's not some bias against Perceivers; I simply find that with a plan, one can achieve more, and one is very rarely susceptible to doing things one should not, because one already has a plan. Without a plan, one feels without obligation, and hence free, to do what they want when they want. With a plan of action, guilt that one has not done what one set out to do ensures that one does it; in other words, one won't go off the rails. Essentially, you're forcing yourself to adapt to the task at hand as opposed to taking the Perceiver's route of adapting the task to one's mindframe. I'm not saying it's "bad" or "worse" than what the Judger does; it's simply less effective in getting things done IMO. Perhaps the Judging route sacrifices low stress levels for a more accomplished life. I don't know. That's another topic.
ETA: One other thing to mention is that I'm not implying that Judgers do a better job of what they do than do Perceivers, or even that it is equal to the Perceiver's doing a job. The Perceiver might well do a better job. All I'm saying is that Judgers are better at doing more stuff in a given amount of time because they have structure.