I thought they stopped using those giant, straight trenches. They are easy to make quickly with machinery, but they don’t have grenade sumps, instead funneling the grenades right to the occupants; and are also so damn wide that it’s easy to get a grenade into the trench. Furthermore, since they are straight, shrapnel doesn’t stop quickly at a bend, it is able to just continue down the line.

I think hiding in a treeline is better than being in this trench, as the treeline at least gives you concealment and doesn’t actively funnel grenades toward you.