In my opinion, there are certain advantages and disadvantages associated with using a 20 day breakout. The advantage is that, if a trend does emerge, you are getting in closer to the top floor, and riding it down (or vice versa). The disadvantage is that, by doing so, you are often getting in before a true trend has emerged, which may increase the probability of being whipsawed.
To develop a scan, similar to what the Turtles would have used (although they traded futures), you would have to go to Stockcharts.com, and get it to look something like this:
In any case, I will continue to pursue 52 week highs/lows, and 26 week highs/lows, but will throw in a few of these 20 day breakouts from time to time for diversification purposes.
The stocks below are examples of 20 day breakdowns:
