To me the question boils down to, "Do you trust YC to have the right people reading your application to make a good decision?" I know that they have high enough volume that it makes no sense for pg to make every decision personally.

What I just read is, "They have found a way to scale higher and while sticking to high quality people who have direct experience with what you want to do."

That makes the answer to the first question a "Yes". :-)