Just for my own edification - I've been digging a little into promotion rules. It seems like it would be possible to make a promotion rule that said something like "applicable by admin user only". Is that not a reasonable rule for some reason? Would the problem be that it could potentially get cleared by later updates or become invalid if a user modifies the order?

The promotion rule doesn't have access to the session to know who is applying it. You could use the "created_by" or whatever that field on the order is called. That would be the admin user if the order was created by an admin, so if your use case is orders created by admins, then yeah that could totally work.

Got it. That makes sense. Thanks a ton for all the help here. Still feeling my way through a lot of this.

You share your name with a pretty scary hockey player so I have to help you.

Lol - I'm not nearly as scary as he is. 🙂