Not sure if you have actually read the article Jim.

The main point is that the prices flutuate according to people's analysis, and different people think differently, which makes price move, sometimes in unexpected ways.
This is not the equivalent of "Crowds be mad".
And also does not negate the validity of value investing.

Let's say:

Investor A is investing for the objective of maximizing return in 50 years - He wants the highest return possible, and probably does not care so much for volatility.
Investor B is investing for maximizing the chance of reaching $10k for this mom's surgery. If he has $5k right now and 2-year horizon, he needs high volatility. That's a mathematical need.

Both are rational. And both will price the same assets with different prices, because they want different things.