How bad do things have to get before Deloittes didn't sign an audit report?

In the case of Adelphia it was this bad apparently - and note that the slides I link to are official training material of the American Institute of Certified Public Accountants - the lead institute in that country.

How much did that cost Deloitte? $167.5 million. That's serious money.

I wonder, when will the Big 4 learn that megalomaniacal entrepreneurs are bad news when allowed to run major corporate entities? I guess, at present rate, only when the cash runs out. Which doesn't say much for their ethics.