From a shop perspective...So what if an engine builder who IS competent tells someone much less knowledgeable "Sure, I can do that!"...takes your money and then blames something else as to why it blew up or didn't make the goal.
There's plenty of "pioneer" left in me but due to what I know...there's a limit to how far I'd try pushing a stock block because I don't have money to burn yet. I'd like to be able to enjoy it long enough to do what I want it to do. It's caution based on knowledge and experience. Perhaps there will be an aftermarket block capable of 4+ liters one day like the Buick GN guys have around.