OK, I'll temper that advice a bit, then. I'm assuming you mean the Mitten, since Yoopers usually state that explicitly. I've run a lot of Michigan trails, especially in the Traverse City/Petoskey area.
1) Michigan hills are runnable. Most trail races in the northeast focus on steep terrain that doesn't exist in MI. I would still say to temper your pace on the hills.
2) Right, but you can't possibly process every stick or hole fast enough, consciously. You need to keep your eyes up and scan the trail, and let your brain subconsciously provide the signals to your legs. Most fast road-runners transitioning to trail running stare at their feet and slow WAY down in hard terrain. Start by running technical terrain slowly, and trying to stay loose and look ahead. Your brain already knows how to do this, you just need to adapt it to trails. I come from racing cars and motorcycles, where this "looking head" is at the core of things, so it's natural for me to think in those terms. Most good trail runners do this well, but don't know they do it.
3) Same as 1) - think of it as even pacing. If you coast on the downhills and attack the uphills, you're just pacing the race very unevenly, from an aerobic point of view. Top XC coaches preach patience on the uphill and attacking on the down for this reason, and MI hills usually have smooth, runnable descents that favor a fast pace. You just need to focus on smoothness. If you get back and brake with your feet, you'll blow your quads up. If you attack and let your legs spin fast under you, pushing off with your toes, you'll find a balance where you may not be accelerating down the hill, but you're not braking any, and the only energy you're expending is flinging your legs back and forth so dang fast and far.
Go to Sleeping Bear Dunes and bomb laps on that first huge dune by the parking lot. Learn how to open your stride and push off down the hill in that very exaggerated environment, and it'll help you a ton. Plus, it's SO MUCH FUN!
