Originally Posted by Campag4life

OP...Its not a bandaid. Top riders pretty much all ride with a setback post and they don't ride $10K bandaids.
Its about weight distribution and fitting a larger rider to a smaller frame. Most top end bikes that come with proprietary seat posts which only fit that frame run about 20-25mm setback and it is part of the equation when being fitted for a given frame. On a smaller frame moving rider weight a bit rearward helps front back weight distribution because if you think about it...riding a smaller frame to achieve the necessary cockpit length for would have too much weight over the front wheel...not good for descending either. A smaller frame for a given rider size is both lighter with typically better standover and has a shorter wheelbase for quicker handling.