Dating requires initiative and interest in other people, so I'm pretty sure INTJs and INTPs don't date each other I only know a few in real life, and although we value similar things and have complementary thinking styles, I've never felt any "click" with them.
"There's no need to be embarrassed about it, Mr. Spock. It happens to the birds and the bees!"
What do you find difficult/eacy to deal with with your partners opposite J or P-type?
Difficult: He needs to prolong every decision making process - not making a decision is the ultimate decision. He has no sense of time and has difficulties respecting deadlines. He refuses to be in a rush, even when it's necessary. He doesn't not want to confront problems immediately or when they arise - he needs more information and time. By the time he's done processing, I've already implemented the changes. He does not enjoy being pushed or rushed into anything, not even fun stuff! Also, sometimes when I make him do something for me, he can give me grief about it like weeks later - I'll ask him to turn off all the lights in the apartment, and he does immediately without any sign of resentment. After a week or so, when he's had time to think about it, he gets pissy with me for making him do it. What the what? Usually there's something wrong with my tone or the way I asked. And also, the eternal open ending.
Easy: He's very easy-going, relaxed, chilled, mellow and does not panic or stress out easily. His P-ness calms Me, if used correctly. He does not compete with me in the decision making hierarchy, most of the time. I enjoy his randomness and unpredictable answers/actions. He does not encourage my need of planing way ahead, which could bother me to bits and make me want to rip his P-ness apart, but it's actually kind of liberating.
How much does it cause conflict v's provide support for skills you are less developed in?
It's all good. I could usually manage to turn conflicts into constructive lessons and I do need to calm the fuck down, sometimes. They do lack some initiative, but that was alright cause I had enough for the both of us.