How you know it is possible? Have you done it or know of anyone who has done it?
I don't trust these youtube videos unless I see them doing it in person. You do know that many people actually believed that Chris Angel really walked on water!!!
I understand that every firmware upgrade process has a component of risk, but in this case the risk is multiplied times ten. This so called firmware upgrade has not even been released by the company, so how to ascertain its authenticity? Even firmware upgrades released officially by a company is risky, for example, when WD earlier released a firmware for WDTV many consumers ended up spoiling their players. How much more risky would a non-official upgrade have to be?