Internal reviews / disclosure mechanisms sound a bit dark to me, the power balance is unhinged. Imagine having a novel idea outside of work, putting some effort in at the weekends, only for your employer to absorb the idea because you naively disclosed it. I can't see any benefit to this system at all for the employee.
In my experience these reviews are not technically detailed, so much as about scope. The closer what you want to do is to what your company does, the more detailed the discussion is likely to be.
> I can't see any benefit to this system at all for the employee.
The real benefit to an employee is to have on paper agreement that they can proceed with a project without fear that the company will claim it later.
I suppose it could be done terribly, but my limited personal experience (on both sides) it's been fine.