The best brain power a human possess is subconscious-- its all the perception that allows you to run fast around moving people and catch a ball. You can do it but you can't explain how. You can probably train yourself to be good at finding water or reading people but you might be bad at explaining why. Worse-- trying to explain yourself might be forcing you to use the feeble symbol processing power of your brain. So a prop helps you feel your way.

Still-- total bs.