[quote name='Vinny']I found run and gun to be useless on crushing since you can die within 2-3 seconds if enough enemies are around. Boreno is probably the hardest part about crushing, especially when you get to the sunken ships.
The best advice I can give you is to stay away from enemies, take cover, and only fire in short bursts. Try to take out the enemies closest to you first. A handgun is really useful since you can get headshots pretty easily. Whenever a new batch of enemies show up, try to use a grenade to hit as many of them as you can (remember, you can aim your gun and then throw a grenade so it'll go real far).[/QUOTE]
Agreed. If you are under fire for like 2 seconds in the open, you're already dead on Crushing. You need to just be patient, and if enemies get close, blind fire. Borneo was actually one of the harder areas on Crushing for me, too.
One other bit of advice is try to kill as many people as you can with Stealth, as it seems that they don't detect you any easier on Crushing than they do on the easier difficulty levels. I finished almost the entire snow level after the train crash this way.