I think the issue is if you are going to order a million toilets, then moving all the risk to the contractor is fine. If you are asking for innovation and R&D, then the contractor already has a ton of risk. Add in requirements to make a fighter suitable for all branches of the military, and the risk is gigantic. In that environment, you need to remove risk from the contractor.
This is why R&D projects can't be treated in the same way as delivery of well understood tech that simply needs to be mass produced well and efficiently.
This is why R&D projects can't be treated in the same way as delivery of well understood tech that simply needs to be mass produced well and efficiently.