I haven't toured in grizzly country, but have spent considerable time tent camping in it, and lived in Alaska several summers in moderately remote areas.

My precautions:

1. Cook meals away from your campsite.
2. Store everything remotely attractive to a bear in a bear canister, hard-sided vehicle, or bear box.
3. Have a set of sleeping clothes and use them religiously instead of clothes that you have worn while cooking. (Or vice-versa, have just cooking clothes, but that's pretty hard to do.) If possible, store all other clothes outside your tent, preferably in hard-sided storage container. If not, hang backpack or stuff sack with clothes, etc., from a suitable tree (if available, not generally in Alaska). When car-camping in grizzly country, we would put everything in the vehicle overnight except for our tent, sleeping bags and pads, and our sleep clothes. If traveling, we would stop and cook dinner before we camped, and then travel some more and camp for the night (e.g., when driving the Alcan).
4. Bear spray.
5. Make plenty of noise in dense brush in grizzly habitat to keep from surprising them (this seems to have been the causal factor in this mauling).

I've seen photos of grizzly maulings from nurse friends of mine in Alaska. Not pretty. But better than being dead.

Really a shame for the victim here. Sounds like he wasn't really doing anything wrong, per so, just surprised the bear. Biking (especially MTBing) is especially problematic for this, as bikes are moving so fast that even if the bear realizes you are there, it probably doesn't have time to leave the area before you show up. There's a good chance that the bear may have been protecting a food source (kill), but the article makes no mention of that.

By the way, a much better article is in the local Flathead news: Grizzly Bear Kills Mountain Biker Near West Glacier - Flathead Beacon

Easy for me to judge since I wasn't there, but it sounds like the "friend" didn't even try to help the guy being mauled, distract the bear, scare him off, or whatever.