I agree, plus the human need for tolerable levels of loss or drawdown. Theory is one thing, but what you can endure is another. I keep mentioning this about my own system, hard to endure 19.6% draw unless you me. *and I won't be dancing a jig either)
I beleive mvp has beat sp400 each and every of its 10 year backtest, also no down years.
You CAN time the market!
But only after you trash the big 3 myths.
Myth 1 - its possible to get every point of every move
...Myth 2 - you'll never have a drawdown
......Myth 3 - you'll never have a loss