I didn't actually have much of a problem with the silo, but I was only playing it on Hardened. I'm now almost there on my Veteran run through. I was just trying to picture how smoke grenades would help from on top of the SILO...
In general, smoke grenades if used wisely can cut huge portions out of the game and what you need to do.
So far, the hardest portions I thought were when you were riding on the lorry to get back and pick up the wounded soldiers...took me forever to kill that tank without blowing myself up... and the D-Day invasion.
I too had tremendous trouble/fun diving around in those trenches. That was the first board I did on Veteran, and with the Bass cranked up, my screen/controller/and whole room shook with each mortar blast!