To be clear Sachin is not talking about setting up an LLC or an S Corp. He's talking about setting up a C Corp, probably in Delaware, for a start-up where your immediate intention is to go out and raise funding.

Service businesses don't apply and neither do bootstrapped web apps. If you're doing one of those go ahead and form your legalzoom llc or s-corp and get the worry out of your mind.

There's a reason YC and others want you to wait and its because untangling the mess that self-incorporation can create is a needless and sometimes expensive time sink when preparing you for investors who are used to dealing with this specific case.

I'm not sure Sachin's part about needing a good lawyer for introductions is important but the part about doing incorporation for a C Corp raising money correctly is a proper point.