You can't practically do nontrivial computation with homeomorphic encyption and the overhead would be much greater than just computing the result 3 times (think

You can't practically do nontrivial computation with homeomorphic encyption and the overhead would be much greater than just computing the result 3 times (think at least 10,000 times slower). There's no generic answer to this, your controls and incentives need to be matched to the type of problem you're trying to solve and the interests of network participants. For example, seti@home "worked" despite waste, mainly IMHO because you got an awesome looking screensaver out of it and you got to tell people your computer was searching for alien life. The leaderboard rankings also were also a great incentive for the types of people who had control over a lot of compute.