Funding on large science projects that I've seen, at least how the NSF does it, "filters up" where the proposal is passed through technically aware committee be

Funding on large science projects that I've seen, at least how the NSF does it, "filters up" where the proposal is passed through technically aware committee before being passed up to less technically aware people. And there is also the P5 committee which makes high-level recommendations about general directions and projects that can more holistically drive "important" (or at least what they deem to be so) science goals forward, where their advice tends to guide many levels of the funding process pretty strongly (if your proposal gets a low grade from them, you aren't getting funded, period). At the level of really big science, this "filtering up" process will go all the way to Congress, where of course you then have people with average-zero science knowledge making a final decision. But to get to that point, I'd wager most if not all science proposals will have passed many valid technical hurdles presented by knowledgeable people.