I'm thinking of non-technical people though. Scientists, being very specialized, would have a somewhat harder time switching research pursuits. Activity by subfield X scientists/pseudoscientists as a group could thus come under a fairly strong incentive to not cure the disease (or at the very least to not accept significant costs to themselves in pursuit of curing it); fortunately they are rather moral on average and (more importantly) have strong incentives as individuals to do good work.
I guess what they have is mostly non-technicals.
This is perhaps a good reason for a relatively authoritarian or steeply-hierarchic structure in grant-giving. I assume most of the study sections at NIH (that give out the dough) consist of rather few people. Perhaps it would be wise to give some formal acclaim to the people that voted to fund a project, if it causes a breakthrough. I assume they get concrete perquisites if they perform well in such a way, in addition to the fact that they'll be like "damn I'm good and everyone knows it", which itself is no mean perquisite at all. When there are fewer people holding the power, the concrete and abstract perquisites of doing a good job will not be spread as thin, so the incentive they exert is greater. Whereas the incentive that researchers as a body have to not improve the treatment of a disease, or to not accept personal costs in exchange for improving it, is the same no matter how the study section's power is arranged.
(That whole strain of analysis is pretty typical of "anti-bureaucratic" political thought.)
While I do think scientists are quite trustworthy and upright on average, that doesn't mean they don't respond self-interestedly to incentives at all. I'm sure that they do.