@pritchet74…..are you familiar with the fairy tale about the princess and the pea? My take on it is in line with this story. Crank arm bending probably contributes to only a small percentage of the total drive train flex that the difference between the stiffest and flexiest crankarms would only be detectable by a princess Taking the insert soles out of your cycling shoes would be more noticeable. This is just my opinion. Mathematically however, the difference in lost power between the stiffest and flexiest crankarms is real and could make all the difference in winning or losing in a very close finish (a tire width in front).