I think the way McVay handled the preseason will get a lot of attention this year.
What won't be analyzed as much is what he did to get them ready. That is the secret sauce and is harder to replicate.
I do think offense has gotten sharper each week and is just hitting stride so I think the preseason reps would have helped in the first 2 games but I agree that the benefit does not out weigh the potential for injury. I also suspect that most teams are getting sharper as the season progresses so I think the benefit is minimal.
As far as I am concerned they got the preseason reps during the first half of the Raider game.