sga,
Don't let me talk you out of going to interviews, but allow me this.
I don't know how PDs decide to rank their candidates, but I do know a little about hiring and firing in the corporate world, as this was part of what I did in my life before medical school.
I can tell you that one of the most significant parts of my recommendation on whether to hire someone was based on the enthusiasm I saw. Often, I would recommend hiring someone with enthusiasm for the job over a better qualified applicant on paper.
On the other thread you posted about an IMG who had 15 interviews and 3 prematches and went through the match and didn't end up getting a position.
Looking at the matchoutcomes posted by the NRMP
http://www.nrmp.org/matchoutcomes.pdf on page 53 one can see that one applicant in the 'All Others' category with more than 15 contigous ranks failed to match. There are also seven applicants with 15 ranks who failed to match.
I can think of a couple reasons for this. Most obviously, that they interviewed poorly and their paper qualifications weren't reflected in the interview. But, I can also see where after interviewing for the nth time, they got jaded with the process and couldn't generate any enthusiasm for that program.
I only say this, because by going 200% you are running the same risk. Look at what you wrote above about one horse towns and IMG sweatshops. If you can't generate enthusiasm for the programs you are visiting and you are simply using them as a back-up to a back-up because you are afraid of not matching, I can see how psych PDs might pick this up and rank you accordingly.
You see what I'm trying to say?
Good luck.
BTW, I'm up to six as of today, thanks to a couple one horse town programs.