Well, I'll offer a couple of "excuses"...
1. Denver was playing a 3-4, which is traditionally a difficult D to handle if one is not experienced. We certainly lack that on our O-line. With a 3-4, the D can rush 4 and it won't be obvious where they are coming from pre-snap. With basically rookie centers and guards, there is a lack of experience making the blocking calls. Hell, even a vet center is challenged by a good 3-4 scheme. Throw in a few zone blitzes and the O-line starts seeing ghosts. They don't know where anybody is coming from.
2. Denver has a new D-coord, who is breaking in a new 3-4 scheme and was probably playing much more aggressively than most teams play in the pre-season. We saw a lot of stuff that one might not normally expect in Game 1 of pre. I think he's trying to get his guys up to speed ASAP, and we got the results of it.
Frankly, it was a supreme learning experience moment, if the team approaches it right. Yes, Cable seems to suck and teaching pass blocking techniques, but our guys need to work together as a unit for a few games before they will be anything more than barely adequate.
Oh and our run blocking was nothing to write home to mom about, either. Without our running game purring to generate that extra half step on pass plays, we're in trouble. The 3-4 has it's own unique troubles in the run game, too.
It's probably a good thing we saw the Broncs this early. It didn't cost us anything for the lessons in how to handle the 3-4. This should help us against the Lambs when we get there. Hopefully it is enough when added to how we do in the next 3 pracitice games.