A lot of people can't run a 4:45 mile, but if you expect to be competitive at a world class level in a marathon, you'd better be able to hold that pace for 26.2 miles.

Isn't YC's situation more akin to asking the marathoner to keep running a few more hundred miles immediately afterwards?

Or rather, demanding that in order to be allowed to run the marathon they have to do 3 mile in 3 minutes sprint... one right after the other with no rest in between.

It probably like running a marathon every day for a month. Some people CAN do that.