Of course having longer legs (longer stride length) makes you faster, IF you can finish your strides in the same amount of time as the ones with shorter legs. Now that's a big IF, but not impossible. Some sprinters have an anatomy/muscle made-up that allows them to generate the same force/speed as others in less time.
An optimum leg-length range (for normal range of muscle anatomies) is not valid if somebody has an exceptional anatomy otherwise regarding muscle contraction.
An extra-long bat would be great, IF you manage to generate the same bat speed. Most players can not, which causes there to be a small range of bat sizes that seems optimal.
What SVR said in his post was perfectly valid, so your saying he 'fails at engineering' and not understanding of the subject matter is not only rude, but you're making a joke off yourself.
By the way, Carl Lewis was also quite tall for a sprinter (6'2) but generated remarkable turnover as well (yes I know he doped).
By the way, apparently Usain Bolt's turnover is not higher than others, but he manages to generate contact pressure of the ground in a shorter duration, which means his contact time with the ground is shorter than opponents.
I still assume Bolt is doping though...but his anatomy does make him an exceptional sprinter, doped up or not.