I understand the barefoot running theories and I support the philosophy of running unshod. However, in practice, this doesn't work for most people. The most basic and common hurdle is concrete & pavement. I don't have ready access to lots of trails, and I am not running around soccer fields to get a 15 miler in. I don't care, I'm changing up the scenery. The OP had quite a few good points, but one thing unmentioned that has been brought up has been the shoe contracts that seem to be the only reason that world-record holders are wearing shoes. Again, on face value, this seems to hold water. But when we look at real world applications of this, and include the higher financial incentives, we see a darker picture. Athletes since the times of Viren, Ghammoudi, all the way up through the present day Bahrainian and Russian athletes have been doping. Not all. Not even a majority. However, athletes are willing to inject themselves with chemicals and other additives that are jeopardizing their long term health for a few years of glory. Does it ever occur to you that if the key was merely TAKING OFF YOUR SHOES every couple days, they would have been doing it? They are willing to jeopardize their, as you put it, "multi-million dollar shoe contracts" (by the way, there are very few athletes making that kind of money), to be the best. To just gain a couple tenths of a second is all it takes and they are going to dope instead of do their training barefoot?
When does Nike make their money on an athlete? Not in training. They make their money on the track or on the roads. With flats that are glorified socks, and with track spikes that are one million times more efficient than barefoot on a track. Their long hard miles training when few people are around is not where they are worried about them slipping off their shoes and running a couple miles barefoot on open fields. These guys will do anything, ANYTHING, to gain a competitive advantage. I'm sorry, but if the shoes that these guys are wearing are holding them back, then all this doping is unnecessarily risking their health and financial and sporting futures.