I've been playing in this space with some success, bringing operators, SMEs and the primes (design leads) doing the work together, like I learnt to do seeing it done back in DMO days, to inform the design, ensure there are no surprises and manage expectations. Senior PMs and PDs hate what I am doing, you see, you can't actually work with the various stakeholders, you need to keep them separate and control the flow of information, be able to blame others and shirk responsibility and accountability by referring to the contract.
Operator input is critical, but they should not dictate the solution or how the contractor does their job.
The biggest issue I have had is when operators and CoA PMs misunderstand a contracted deliverable, because they are not subject matter experts, assume the contractor is incompetent or not doing their job, and go on the attack. They don't listen to industry, they don't listen to independent SMEs, they don't listen to their own technical specialists, they think they know best, and they pull out their biggest stick to bash the contractor into compliance while silencing everyone who is trying to explain to them that they have misunderstood because they lack the prerequisite knowledge to understand.
I waste more time convincing people that things need to be done, or that they don't actually matter, than I spend doing what is supposed to be my job.
Long story short, get the incompetent project managers and project directors (most of them are little more than admin people anyway, but admin with power) out of the decision chain, engage operators as SMEs, support design, build, and T&E, but not as decision-makers, and let the clever kids do their jobs without amateurs undermining them.
