In reply to dave_59:
I like your example of the “solve before” constraint; very clear.
I was getting hung up on the fact that the implication operator is not bidirectional, while forgetting that my other 2 constraints were responsible for shrinking down my solution space such that there were no results possible for: E.g SET2 inst=1, or SET3 inst=1.
Illustrating the solution space helps a lot; sounds like the key is being able to look at your constraints to accurately determine the solution space. Then, it would make the job much easier of seeing how in-line or additional constraints would then shrink it further, or affect the distribution in the “solve before” case.