I have been doing stronglifts for half year. I only stuck with a completely primal diet for a month and it worked fine. As long as you can get plenty of calories your fine. If I could afford to eat the 5,000+ calories and 200g of protein primal style all the time I would be doing it. Now I eat primal about 75-80% of the time.
Yes, you do have to be careful, but I'm self-taught lifter and I haven't been injured yet. Mehdi, the founder of stronglifts, has videos of himself performing some of the more technical lifts on the website along with instructions. My deadlift is only 315 x 5 but I think I would have injured myself by now if I was doing something wrong. So as long as you take the time to learn the form properly you should be fine.