> or else they wouldn't have explicitly said it was obvious to them (speaking as an engineer)

I’m sorry but you might consider patenting your mind reading device.

It seems pretty easy to imagine engineers spending week/months/etc. solving a specific problem the solution to which might seem pretty ‘obvious’ to them when they actually manage to arrive at it. That doesn’t necessarily mean it’s actually obvious ..

> wouldn't work to just provide that context to resolve the matter

Why take the risk? And even if you end up winning at the end having to prove something like that will still result in additional costs and/or delays.

Your reasoning seems to be based on vague assumptions based on a very vaguely described situation. I find it hard to understand how can someone feel so certain about it with close to zero real context.