This thread aims to show those of you who don't and wish to know why MBTT doesn't work why it doesn't, and why it can't be correlated with socionics.
Essentially, the reason it doesn't work is because the methods of typing are confused. And when there is more than one way to determine type, that is when the trouble starts.
In MBTT, there are two ways of determining type:
1) Dichotomically (the most common method)
2) Functionally (closer to socionics)
Now, say you take a test that determines that your type is ESFJ. How did the test determine you type? It tested you dichotomically, based on each of the E/I, S/N, T/F, J/P dichotomies. Now, convert that into functions, and your functions should be Fe leading, Si secondary. Does this have to be the case? Well, for the theory to work properly, yes. Simply put though, it doesn't. Why? Because Fe leading, Si secondary necessarily has to be the case for one to be ESFJ, and it isn't necessarily the case. You could, for example, be on the S/N border, and what does that mean? Your Auxiliary function could just as easily be Ni as it could be Si? Furthermore, if you try correlating this with socionics, you're essentially purporting that what the ESFJ's socionical equivalent - the ESE - could easily be an EIE, which is bullshit. How could someone's creative function possibly be their potential PoLR? It couldn't.