Indeed set the expectations
See expect it to do this, we expect it to be available by when and we expect not to have to spend more than X.
Now us propeller heads can come up with a set of options within the current constraints. If you've employed competent people (if you are employing incompetents then nothing you can do is going to matter), you will get a set of achievable options with costs and benefits, and then the most viable one can be chosen.
Any negativity will be limited to within the IT team itself, and should be addressed there.
All the major constraints and expectations have been set and are to the best of everyone's knowledge at the time, sane and therefor achievable.
What we keep doing and I do mean we (not them or us) is getting it bass ackwards.
Constraints and expectations are set, important people invest their reputations in the result. Then when you challenge the idea, they will take it as an attack. They have no choice, no manouevering room. it's too big to not to succeed.
Standard corporate (and government) practice kicks in, failure gets dressed as success and in a completely unrelated event a couple of little guys who who foolishly keep insist on saying we was right, are let go because they are a bit negative,
Everybody around them sees this happen, just because they aren't managers it doesn't mean they are stupid, so they don't rock the boat.
So despite all the claims about not wanting sycophants, they engineer an environment where it's a good career move...
