It's dangerous when it leads a person to choose "I'm going to figure this out on my own" over "I'm going to find someone who can solve this" in cases where they really should have known to pick the latter.

Watch what happens when you let the post doc PhD "help" set up a scan in the MR scanner. It's amazing/terrifying what a very clever person will do in an unfamiliar environment with different rules to the real world.