You know, I remember reading that the reason they started Block magazine was because some people wanted written instructions for all of those YouTube videos, and that just watching the videos (even though they're free) wasn't quite enough. Different strokes for different folks, I guess. I enjoy watching the videos but I'm also happy to know that eventually I'll get the magazine so I don't have to stress about writing everything down.
As far as the time it takes for the magazine to arrive, I don't think it's a matter of them being over-extended. I think having the subscriptions paid for ahead of time gives them an idea of what their print run should be. Unsold magazines won't benefit their bottom line; those are the enemy of any magazine publisher because it's money spent with no return. As folksy as they are, they have to make a profit too! More power to them, I say.
I love Block and will be a subscriber as long as it exists. Can't wait to sit down with mine tonight and enjoy it (just arrived today).