I'm really not sure what their plan is with the ranged enemies? It feels like they changed tack half way through it or something?
So the tutorial says sprint and slide to avoid enemy fire but it...doesn't actually work that way? Enemy lasguns and such do so much toughness damage you're instantly staggered if they are hitting you, which if you're an ogryn is all the time because there is no cover big enough to hide behind. Once you get past the two wiener difficulties you can't even try and approach a group of lasgun enemies if they are down a hall behind cover etc, they'll just shred you before you get there.