Yes, I believe you about the studies, I have read them, too.
But remember, I'm on steroids, which slows downs catabolism and actually enhances muscle protein synthesis.
I have no reason to lie to you, as you can see, I don't see any "pills" promising to build muscles in a week. I'm not lying to you.
As for the pump effect, it's not pump. After training, the pump goes away in a few hours and then these is a noticable increase in muscle size in the next days.
It probably could be so-called newbie gains.