[gruseom]

I am curious what PG has to say about this.

You're in luck. From the link tomblomfield supplied:

"Actually it would be better to expend that effort on your company or the application. Don't spend a lot of time spamming YC alumni trying to collect recommendations. They don't carry any weight with us unless they are very strong. We can tell the difference between a recommendation that's being made for our sake (because the alum thinks it would damaging for us to overlook the application), and one that's being made for the sake of the applicant (e.g. because the alum is benevolent and they begged him to recommend them)."