Some of that proves trend-following worked many decades ago, before everyone had access to free charts, Excel spreadsheets, relatively cheap backtesting/system-building software, etc. It was in the early 90s when those things became more available (at least EOD charting and backtesting) that trend-following fell apart. The vast majority of hedge funds don't beat the S&P 500. That's my point. Look up the funds in Covel's book and see how they've done since it was published. I have nothing against trend-following and use a little of it personally, but only with a few other models as filters.
Hedge funds are like elephants in a pond. They cannot move hundreds of millions of dollars getting into and out of positions like retail traders do. It takes them months to get their entire positions. That is why they have to be satisfied with 18-20% per year. Jesse Livermore was trading then, with a couple million, Nicolas Darvas was trading with thousands then, tens of thousands which he grew to over $2,000,000, Richard Dennis employed like 13 turtles who traded his monies, the better traders got $1,000,000 a piece still, he earned like over $400 million thru the efforts of his turtles. At some point, you reach a wall where huge amounts of cash become a huge problem getting the same results. You cannot move huge amounts of cash trading and affecting the share price you pay to enter and exit your trade. Retail traders do not have that problem. I use only trend following in trading both stocks and options.