The versions I’ve taken had scores for the traits. The I/E trait was the only one on the fence. The rest were solid in the NFP categories.
OK, that’s a perfect example for me. If I give myself or a client a deadline, or promise anything to anyone, I follow through with it. Almost without exception. If somebody asks me to do something, and I promise I’ll do it by so-and-so a time, I will do it by so-and-so time, and it will be complete. So I’m completely in the ISTJ camp there.
However, I feel I’m also completely in the ENFP camp. If I don’t give myself deadlines, if I don’t make promises, if I just set up vague projects for myself with no hard-defined goals (which is for a lot of personal stuff), then I very much am a start-something-never-finish-it type of guy. Anything that falls under personal projects that don’t involve the expectations of others falls into this camp. If I want to give myself a personal project and assure that it will be done, I have to give myself a hard deadline.
So, there’s one perfect example of how both those descriptions apply accurately to me.
Sure, and that probably applies to anyone who’s worked in a company for more than a month or so without getting fired. My comment above was “To some degree, society and work train people to behave in certain ways, so over time you can learn to behave differently no matter your innate personality” and I meant that directly in regards to this.
Your personality is just a vague guideline; it can be overridden either consciously or habitually. But which mode of behavior comes most naturally to you? It’s not about what you’re capable of training yourself to do, but what comes with the least effort.*
Like you, I have to essentially promise something or be given a hard deadline to finish anything. I start a lot more projects than I finish, haphazardly switching between them and not getting much done. To my understanding, not everyone functions this way – some people might only focus on a few and obsess over them to completion, perfection, and beyond. We can learn to operate like them or they like us, but it’s not what they would usually do.
*The caveat is, of course, that what comes effortlessly in part depends on how much you practice it. In that sense, people’s personalities can be modified through repetition… introverts can become extroverts with enough practice, etc. Whether that’s betraying one’s true self and pretending to be someone else or simply changing one true’s self, I don’t know. Personally, I view these things as more descriptive than prescriptive, and certainly more entertaining than scientific, more “Hmm, interesting” and less “Third law of INFP says…”.
Both, honestly. The literal statement: “The ISTJ is extremely dependable on following through with things which he or she has promised” is true.
And, even that aside, it depends. There are some projects that will completely engross me to the exclusion of all others. Other times I will vacillate between various diversions. I can’t honestly say one describes me better than the other. I will tinker with a lot of things, and then obsess over things that, for whatever reason, grab a hold over me.
Thus, I take these things with a grain of salt.
I believe you.
But hey, if you really don’t like the MBTI, there’s always the DSM 
Clearly the tests partition people in a predictive way. Are you claiming that the partition is too fuzzy or arbitrary, or instead that the predictions, however good, are rarely useful?
I recall reading that opposite M-B types tend to make best spouses. This agrees with my personal experience. Anyone know good websites for statistics on M-B types?
To answer OP, I score as INTP while many Dopers seem to be INTJ. A difference was brought home to me in a SDMB thread about the Shakespeare Authorship question. I said I was agnostic and open-minded on the topic; the response I got was that I had to be insincere: no one was agnostic about Shakespeare Authorship!
Well, I suppose I could have dissociative identity disorder, which is why all the classifications seem to apply to me. But, also, when I read the questions on the Myers-Briggs test, a good half of the questions I could answer either way, or would prefer a “SOMETIMES” option. It’s somewhat surprising that I do score consistently enough as E/I NTP, but I think part of it is how I perceive myself to be or would like others perceive me to be, rather than how I really am–which neither fits into a binary answer.
I was an INTJ, but there was one of the axes on which my score was right around the middle - either the S/N or the J/P. I need to dig that out. If it’s the latter, I may be a good control group for the discussion. 