Quote from Thunderdog:
Presumably, you understand that a complete trading method involves a combination of rules calibrated to work with one another as a unified whole. It does not involve just slapping together whatever happens to be in the refrigerator at the moment. Presumably, you understand that arriving at a usable system involves testing, tweaking, testing some more and then more adjustment until you arrive at something that is not overfitted and works on balance. As you might imagine, the effort is nuanced and is not measured solely by its quantity. (On the other hand, the production of academic papers is often fueled by the "publish or perish" rule. This is not to suggest that meaningful academic research is not performed, because that would be a foolish statement. However, sadly, there is no lack of academic "scholars" principally motivated by quantity of output, since research grants and other forms of compensation are often dictated by quantity of output.)
Are we to assume that the authors of the study you referenced took the kind of time and care it takes to develop a usable system, to arrive at their collection of 7,846 quantitative trading rules? That it involved a careful collection of criteria that were preceded by careful market study over an extended period of time? By way of example, to be able to prepare a gourmet meal requires more than just a list of its essential ingredients. It is a matter of how and when the ingredients are used that makes the difference. Merely pouring some, all, or even more of the essential ingredients in a vat and then stirring, will likely yield different results than those desired.