"I agree. Of course it is converted, but we talked about the timing. In my opinion (and as stated in the ISTD technique) this conversion is started at the end of the second "quick"
Actually no. The ISTD technique is written in terms of muscle actions, so the timing is given for that of the lowering actions and rising actions. However, the energy conversion is related to the change of altitude which starts before the official lowering or rising action and continues after the end of it. Looking at foxtrot, it's pretty much at the lowest altitude with the legs divided into step 1, and at the highest altitude as the body passes over the foot in step 2, but this is not the timing of the rising and lowering actions.