Ratios can change outcomes as long as strong culling is done with it.
Those who look at ''all stocks'' rather than culled selections from a given area can be misled as to where the happy hunting ground is.
I first formed this view when I read >
Competing for Stock Market ProfitsPaperback – 1 January 1974
byPaul F. Jessup(Author)
Here they found virtually every known portfolio approach known and advertised at the time provided no long advantage at all.
However, they did find something but did not go into details. That something they found was options.
The low price is the thing that options have rather than the 'options in and of themselves'.
Just one example I will give is my buy if TTT at 1.4c having fallen from ~$1.00 or more ie a 98% fall before I bought. Now in the 7-9c area. I looked and found reasons to suspect things could really turn around big time. No need to go into those details. The key is I found real reasons things could come good.
So obviously a few total losses will still see me well ahead of the indexes overall.
Just one view.
I think the author did not want to go into options too much given the risk profile was way beyond that normally considered responsible.
Funny that.... What is normally considered responsible gives very ordinary returns.