How P's survive:
1. Compartmentalize. Put a bunch of irons in the fire so it always sounds like you're doing work and can pass off lack of progress in one task as "intense focus" on another... even if you're just playing Solitaire or posting on forums half a day. Very few people will know your "full" schedule; hence, you can pad it.
This helps... not sure about the solitaire part, but at any given moment, being able to pick and choose tasks helps. I don't think you can count on always having the option - but at least for me, it helps.
2. Do bangup work on the jobs you complete.
Always helps.
3. Sound like you're on top of things and can tell someone exactly what's going on, even if you're nowhere close to being completed with it.
Hmm - I wouldn't know about this one, maybe I should try it... I'm the one who's always secondguessing and pointing out what I *don't* know (yet) about a problem... some of the strong J folks I work with (ie, my boss) *hate* that. They jump in with the "we'll just have to cut corners to make the deadline then" bit (which they KNOW I hate).
4. Build extra time into your schedules, don't go for the bare minimal time -- give yourself room to play and explore.
I think this is the most important one... although don't get caught doing it

. I work in a *very* J sort of environment... they've been pressuring us to "plan out everything you'll do in detail before you do it, assign a time estimate, then do it and record how accurate your estimate was". And they absolutely LOVE to set basically worthless arbitrary deadlines and then act like the world's going to end if they're not hit (ignoring changes that come up, or emergency work on other items). This completely doesn't work for what I do, but that doesn't matter... it's the policy that's important, apparently. I, of course, plan to basically ignore this... and if I can't, I'll overestimate the time up front. If you work in the kind of job where you never know exactly how long something will take, *don't* commit... and if you're forced to, double your most conservative estimate (I mean, if it's good enough for Scotty from Star Trek, it's good enough for me! - kidding... sort of

). Otherwise you'll get screwed. Even aside from that, flexibility is good.
5. Get a variety of job duties so that you can multi-task more when you get bored or stuck.
Kinda like #1, but I agree.
6. Have your resume on hand so you can go somewhere else if you get canned or habitually bored.
I haven't had to do this part yet... hopefully I can keep it that way

.
I always wondered , do you have to be a J to be successfuil in this world.
If you're talking about financial success, no, you don't... but I truly believe that it does help. So many jobs that wind up being "high paying" depend on schedules, deadlines, and not only being able to do something, but being able to tell someone, ahead of time, exactly what *will* happen with the project at multiple points of time... ie, scheduling. Now I'm not convinced that this is necessary to accomplish, but it's an undeniable fact that most industries revolve around this model

sick

.
But there are places for P's too

. Just play to your strengths. And, I should add, don't be too blatantly immune to compromise. Nobody's going to get their way all the time... if you pick your battles you can come out all right most of the time. And when you can't... maybe it's time to look for something else.