I think Jobs was more extraordinary as a businessman than Wozniak was as a programmer.

I don't think Carmack is a jerk so much as he's just, well, different. More like a machine than a human. I guess that could cause him to be heartless at times but he came off as fair.

Romero was important for ID's success, but as the story played out, Carmack was able to find success without Romero but Romero was not able to be successful without Carmack. Read into that as you will.