Thanks for such concise and informative answer, Billy.

From what you write and from what I've read in other places, I conclude that computer and algorithmic trading is still very much in its childhood since it started to develop 10-15 years ago (I hope I'm not mistaken). This is kind of scary, because once quantitative analysis becomes ubiquitous as I think it will be in another 5-10 years, the same information will be spread among all market participants, and honestly I don't know how this affects trading.
Anyway, it's always a pleasure to learn from an experienced trader such as you.