It doesn't fix the flaws. And it doesn't even make the certificate more secure.

You and I agree to some deal. Then we used strong crypto to sign it. We suspect that that's unforgeable.

Now Mike and Steve in Sydney get involved - but how? These guys know neither of us. All they can do is validate those signatures - but that adds nothing, any program could do that.

FYI, here's the original patent from 1979!