Why not then publish the strategies once outmoded, or are they in fact published? Can I go see somewhere what strategies big funds used in the 90s to make bank, which presumably no longer offer a competitive advantage? The way I can go see what computer exploits/hacks used to work when they were still secret?

Maybe it's just what I know, but I can't help but think the "strategies" are a lot like security exploits--some cleverness, some technical facility, but mainly the result of staring at the system for a really long time and stumbling on things.