Came across a little tidbit about changing connected systems (in this case, piping) on a good sized project. It appears that if you have worksets defined by building or structure, and you have connected geometry that is in more than one workset, you need to make sure that you're the owner of all worksets the connected pipe or duct belongs to.
In our case, we've set up an overall site model, that contains worksets based on building and discipline. We had a group of pipe we needed to shift down about a foot. When the tech went to move the pipe, he got an ownership warning (along with the editing request). In this case, the pipe that was being stretched was connected to a pipe in another workset the tech didn't have enabled, so the command fails. enabling the workset eliminated the dialog and allowed the move, even though the pipe being edited wasn't in the disabled workset.
We've discussed doing workset by systems, but this seems to be a little more trouble...so let me know how you're dealing with it - is it better to have a system that's connect across a longer distance in one workset, or do it all by building? (By they way, we also have the yard piping in its own workset, too.)
Ain't this BIM stuff fun...later - dab