Indeed, this will save so much unnecessary memorization of the allowed dimension combinations when entering dimensions. It takes way too much time for new joiners in a company. They enter wrong combinations all the time and get errors after errors. Also if a document is following a long approval chain and the dimension combination is incorrect, it may go unnoticed for a few approvals at least (and rectifying that error means starting the workflow all over again). This would be such a time saver!