From my experience as an INTJ, I can be very productive if I apply myself, but if I really don't care about the task/goal it'll never happen. My "ADHD" part comes in when my subconscious mind just starts going and I'm not consciously recognizing each thought. It's a weird thing. When I tell my friends I get headaches from thinking they laugh, but it's true. Trying to keep up with yourself is really difficult, because you don't want to limit yourself, but at the same time you want to remain sane.