Sure, anything cloud based is right out, I haven't worked at at single place in 20+ years that allows anything in the cloud. I'm talking about Petro/chem engine

Sure, anything cloud based is right out, I haven't worked at at single place in 20+ years that allows anything in the cloud. I'm talking about Petro/chem engineering. SharePoint can be on premises, but that is revision/snapshot based, so the whole document is snapshotted, not individual cells. Within a revision a datum / cell might change multiple times, those changes are lost. Each cell change does cascade other changes in many other documents and drawings so being aware of each change is paramount. Missing a change not only would mean incorrect downstream /cross stream documents but it can result in the loss of life. It's a seriously tough problem with serious results.