OK, 1 more point directly responding.

I think you're actually wrong that prizes would be more politically saleable. In general, it is tough politics for the govt to offer a fixed price for something and then let the supplier keep much larger than expected profits if they can come in way under price. When that happens, they are accused of cheating the govt.

It's stupid -- I actually in principle with Spaceprojects that we ought to do a lot of market-based procurement reform, just not that space exploration is a good candidate for a prize-based strategy.

But the reality is that if the govt says, we'll pay $1 million if someone delivers us an X, and it turns out that Yoyodyne is able to deliver one for $100,000, keeping $900,000 profit, there will be a political uproar. Even if the govt used to pay $2 million to build X itself.

There's a lot less public support for unfettered market transactions than you'd like to think -- just think about the outrage when merchants raise prices for water, gas, etc after a natural disaster, even though that response is a perfectly rational and reasonable response to increased demand and constrained supply.

So we offer a $50bn prize for being the first to land on Mars, figuring a mission will cost in the $25bn range. But, it turns out that the Zubrin I mission is pulled off for only $1bn by using surplus Estes model rocket engines. If so, there will be hell to pay for whatever politician is responsible for handing out that $49bn profit. Yes, Spaceprojects, I'll know you'd applaud the winners for their igenuity and would happily hand them their mountain of cash, but that is not the way most Americans would react.

Even conservatives will complain. Anti-tax types will wonder why the prize wasn't only $5bn if the mission could be done so cheaply; they'll blast Congress and the White House for being snookered. Of course, the whole point of the prize method is that govt agencies aren't good at figuring out low-cost ways of doing something and that $50bn is still less than it would have cost NASA, but that won't change the fact that the $49bn profit would be largely seen as "waste".

Of course you could say that the prize will be the winner's cost plus 50%, or cost plus $5 bn, or whatever, but then you're right back to the perverse incentive structures seen in current aerospace contracting.

Anyway, that's may say, I'm done. Good luck.