> "buy on rumor, sell on news"

Let me stop you right there - stock market is a multi-agent system with autonomous algorithms making micro decisions, cap managers doing strategic decisions, and everything in the middle. Add a bit of chaos theory. "Buy on rumor, sell on news" is an extremely simplified and naive rational for explaining how a stock market works.

Most theories of how a stock market works have a built-in fallacy. If someone figured out how the stock market fluctuates, it would be ironed out by massive hedges.