In most common, trivial real life situations, you have an advantage if you keep spewing forth nonsense and adjust for mistakes as you go along and keep pushing

In most common, trivial real life situations, you have an advantage if you keep spewing forth nonsense and adjust for mistakes as you go along and keep pushing forward semi-blindly - compared to being forever hesitant in search for perfect truth. The "confident idiot" basically applies a Monte Carlo search over the range of possibilities, and may eventually fall onto a good-enough solution. I suspect that's the explanation for the D-K effect. If that's the case, then the "idiot" actually uses a pretty sophisticated overall strategy that works well in a fluid world (so not so much an idiot actually).