The Rational/Irrational Issue

I've heard you just switch the last letters (J/P) in the introverts to go from Myers-Briggs to Socionics or vise-versa. And, this seemed valid because, I am INFP in Myers-Briggs and INFj in Socionics. HOWEVER, when I read the descriptions of what rational and irrational was in socionics, I hit a brick wall. Socionics has the same description as Myers'Briggs for rational and irrational. And I have no doubt in my mind that I identify with IRrational even if I tested INFj (in socionics). INFj is considered rational (which I am not). I took the test many times and came out 5-INFJ to 1-INFP. I've come close to INFP but end up INFJ.
If rational and irrational have the same description in Socionics and Myer-Briggs, then why do you have to switch the letters on the end? If you don't have to switch the letters on the end, then, why did I come out INFj in socionics and INFP in Myers-Briggs? This doesn't make any sense, and it makes this web site seem very unprofessional, haphazardly done, incomplete, incompetent, and not credible. I appreciate this web site's potential, but it needs work. I'd be satisfied if I could at least get some explanation about all of this. If you are unsure of what I'm asking, tell me, and I'll try to put it another way.
Another thing is that there are no explanations of what first tier dichotomies, 2nd, ...etc. mean. What does relative value mean? What does relative strength mean? Could you elaborate on what romance styles (primary: victim; secondary:Caregiver) mean? If rational and Judging is in the "first tier dichotomies, what does that mean?
Thanks
If rational and irrational have the same description in Socionics and Myer-Briggs, then why do you have to switch the letters on the end? If you don't have to switch the letters on the end, then, why did I come out INFj in socionics and INFP in Myers-Briggs? This doesn't make any sense, and it makes this web site seem very unprofessional, haphazardly done, incomplete, incompetent, and not credible. I appreciate this web site's potential, but it needs work. I'd be satisfied if I could at least get some explanation about all of this. If you are unsure of what I'm asking, tell me, and I'll try to put it another way.
Another thing is that there are no explanations of what first tier dichotomies, 2nd, ...etc. mean. What does relative value mean? What does relative strength mean? Could you elaborate on what romance styles (primary: victim; secondary:Caregiver) mean? If rational and Judging is in the "first tier dichotomies, what does that mean?

Thanks