On October 7th, Gregory Maxwell, one of Blockstream's co-founders and one of Bitcoin's most prominent developers, said that people's attention to 51% of attacks is too high, and it has some appealing mystery. In response to the question "Why not reduce the risk of attack by 51% by biting the bitcoin hard," Maxwell said that when people talk about 51%, they are really talking about people manipulating elections so they can use new ones. The order of transactions covers the order of transactions that were previously considered acceptable, and the new order will change some of their payments from one party to the other. With this understanding, you can see that the focus is not even that a single person has too much computing power. If 100 people have equal power and most of them collude and honestly cover the outcome, the attack will be equally effective.