Also, if you put "almost zero" effort into your intro video, then it's going to suck. I don't know what YC is looking for in the video, but it seems like you'll have a higher chance of them funding you if they see that you have at least one naturally-charismatic founder, in addition to a very skilled technical one. The video can show your charisma, just like the application can show your technical skill.
It still seems like the total number of fully-completed applications will decrease because of the video. But again, that's a good thing.
Seventeen year old: http://www.iamthewitness.com/Bollyn/RogerHolyfield.jpg
Eighteen year old Aaron Swartz in 2005: http://graphics.boston.com/bonzai-fba/Original_Photo/2007/09...
Also, I just realized that doing a Google image search for "thirteen year old boy" at a public coffee shop might not be such a good idea.
On the other hand, if you ever wanted to Goatse PG, here's your chance.