I wonder if people are actually able to mistype themselves. I mean, it's all so subjective, thought processes are invisible and incomprehensible to others, and even to myself. Who's going to tell me if I have primary Ni or primary Te? Perhaps I use another "substitute" for my supposed primary function with the same cognitive results, nobody can ever tell. Except for myself. Or maybe not: my "type" may very well be an unconscious preference (choice) after becoming familiar with MBTI.