With respect, did that research involve actual money and an experiment of adequate length, like ten years?
Actually, papers like that are a dime a dozen. Anyone with an IQ above room temperature can find an investment scheme that backtests very well. All one has to do is to follow the advice that renowned financial advisor Will Rogers gave us 90 years ago:
"Don't gamble; take all your savings and buy some good stock and hold it till it goes up, then sell it. If it don't go up, don't buy it."
Thanks to @sengsational, here are some 4-year actual results from another scheme that apparently backtested well:
https://www.early-retirement.org/forums/f44/magic-formula-tracker-82446.html But that is just an anecdote. Here is data:
We have over 60 years of history showing that stock-picker funds produce results that are nearly indistinguishable from random. Worse than random, actually. This includes almost 20 years of biannual S&P SPIVA reports showing that over five and ten year periods only single-digit percentages of stock-picker funds beat their benchmarks. Certainly among all of those funds, there are tens of thousands of analysts cooking up schemes that backtest well. If the schemes were useful, there would be winners whose past performance did in fact predict future results. There are not.
Another to think about is why this Faber guy would be giving this scheme away for free and hustling clients for his advisory service. If he actually had a scheme that worked, don't you think he'd be quietly enjoying life on a tropical island or a private yacht with a helipad and at least one swimming pool? The mere fact that he is on the internet and pitching is evidence that he does not believe in his own schemes.