Its not an exact science, or even close to approximate. It's more for fun than anything else. The correlation between style and personality is 'loose'. And a lot of it is in the perspective of the observer and what he knows about the person upfront. I guess. Consider this a "fun" or "not fun" exercise, and nothing more :)
So what you're saying is that you guess and then rationalize your successes? (If the correlation is loose, you've really got to measure it to know for sure it even exists.)