Jason, for the sake of this discussion let's use the most old-school valuation method -- dividend yield.

Dividends have been the most straight forward catalyst in equity investment. Pension funds, endowments and income-oriented mutual funds all seek for yields. Hence, in long run, stock prices track dividends, not emotions. Emotions can deviate the yield by hundreds of bps in short term, but in long run those deviations don't matter much. A 10% CAGR in dividends over 10-20 years would probably produce a 9-11% CAGR in equity value.

Many researches showed that equity prices track earnings growth over the long term, i.e. if earnings grow by 10% over 10-20 years, stock price most probably will follow suit (maybe +/-1%).

BRK is the best example of stock price tracking long-term fundamentals -- its book value compounded at 19% annual rate while its market value compounded at 20%. If anything, emotions actually produced only 1% price premium to the growth, and that's pretty much a Warren-Buffett premium.