> How many successful entrepreneurs have you heard of without ideas, just totally empty heads and whole bunch of hustle?

We'll find out after this next YC round. Besides, I think the point is that pg is looking for people that are the antithesis of empty heads. Startup ideas mutate, and if you can find driven people with fertile minds and place them in a setting where product ideas can be brainstormed and hashed out with the guidance of the YC team, then they stand a much better chance of success then the typical entrepreneur who might try this on their own.