The craziest conclusion I've seen longevity experts narrow in on is the mTOR == cancer hypothesis. And the logic leaps are astounding:

1. Rapamycin inhibits expression of mTOR. (verified)

2. Rapamycin extends lifespan of cancer-encoded laboratory rats. (verified)

3. Therefore, activation of mTOR causes cancer. (???)

4. Therefore, stop eating protein.

The leap from 2 to 3 is incredible. These guys aren't considering the possibility that Rapamycin might have other cancer-inhibiting properties via other pathways. They're just assuming that because the R in mTOR stands for Rapamycin, that's the only thing the drug does.