Hi Makattack,
In theory yes, you wait for the retrace and buy on the level and sell on the next level.
Me don't understand "why" it works, but I just know it works most of the time. Same as elliott wave.
Normally, if I see a run, and when the run is over due to a series of (lower lows and lower highs) then I would look for Fib retracement level.
