There's a subtlety -- in "100 hours does't always work" you describe how simply putting the time in isn't sufficient to get the outcome. You still tried, and you (unfortunately) failed. In the case of YC, it seems that you chose not to try (though you likely already spent 100 hours for the original interview process, right?).

I think you may want to write a blog post about that: How do you choose which project to invest 100 units into? And, how do you measure the success of that decision both in the short- and long-terms?

For example, do you think the Evernote application had long-run benefits? Did it help you in getting a different job down the road? Those are the kind of stories I think would be interesting to connect to the give it 100 project.

Best of luck on the endeavor!