I don't crossfit, but I do Olympic Weightlifting, round-robin the platform with 2 other lifters. I get about 2-6min rest between sets for about 1.5 hours... spending about 20 minutes warming up, so it's not "medium intensity" at all.
My best training days are when I get into the gym fueled, but hungry. This means that for breakfast I'll have a slightly bigger breakfast (extra eggs, some potatoes (I'm normally LC), fruit, veggies, and meat), then I'll skip lunch and train in the early afternoon.
Thanks to Art DeVany's influence I also avoid eating immediately post-workout as well. I have a 40-min drive home from the gym anyway so I end up training from say, 2pm to 4pm, and I make it home by 5, prepare a meal and eat by 6.
Back in the day I used to focus solely on pre/post workout nutrition. It didn't change my rate of progress or recovery, and that is why I don't even bother anymore. I also found that a big protein shake immediately after a brutal set of 20-rep squats or tireflips, usually would reverse direction fairly quick and I'd have to get a mop.
In a nutshell, I don't eat at least 3-4 hours before, and usually 1-2 hours after I train. This works well for me.