it's possible only in theory. You couldn't even do it in...

it's possible only in theory. You couldn't even do it in hindsight. Try it. look at an interactive chart of any stock for the past 3 years and cover all the the highs and lows to the right except for the first day 3 years ago.
then, on paper, decide when to buy and when to sell revealing only one day at a time. Even with the benefit of knowing how that stock has performed, you won't be able to pick anywhere near 50 10% gains.
i repeat my offer to give anyone half my profit to get me 50, 10% gains in any stock.