Couple of comments…
Overspeed isn’t just any method that deals with faster movement; the movement has to be done in a similar context i.e. high force output. Stick drills are not overspeed, IMHO, because the force output is so much lower. If such a thing could translate, we could just have athletes take tap dancing, because the contacts are extremely quick. But there would be no transfer, of course. Stick drills may be beneficial, but not in the develpment of RFD, stiffness etc., when force outputs are much higher.
Secondly, when counting steps and extrapolating to stride length, you need to be careful since changes in early steps (start phase, acceleration) can influence the number. Shorter strides in the early phase could offset longer strides in the Max V phase making the total number of steps the same, even if Max V stride length has lengthened. A better method might be to estimate the distance being covered with the longest 10 strides in the Max V phase, say somewhere between 60m and 80m, and compare those to earlier, slower, races.