I don't wear ISTJ as my true type. I wear me as my true type. ISTJ just classifies my thought processes into something more readily accessible and understandable.
In about 80% of my life, I put the outer situation at a higher priority than my own feelings. This is very general, but it crosses into career, school, among other things. At work, I rarely take things personally because I make it my priority to follow the rules of the situation and allow myself to follow the situation. Objectivity and clear-headed thinking are my preferred ways of doing things. It's not because it works best, but because it feels good and it's what I understand the easiest. There are other ways to do things, but I don't understand them easily, so I stick to what I do understand.....logic.
I say fuck it to work. Working for the sake of work just plain stupid. I enjoy work because it's directly verifiable productivity. Does it mean I want to devote my life to work? NO. It's just that that part of my life provides fulfillment where other people don't see it. I admire the executive lifestyle and I want to live it. That's the ISTJ in me.