It’s deeper than that - you won’t just look like a “clueless coder”, you’ll find yourself unemployable. I learned early on that it doesn’t matter what credentials you have or how much experience you have, never admit there’s anything you don’t know, or they’ll pass on you to hire somebody else who confidently insists that he does know absolutely every single thing there is to know. I feel bad for the author of this piece, because putting his name to this _will_ cost him employment at some point in the future.