True, but they still attach at the ring in the middle of the sax. A lot of them also have a movable hook, which means i basically would have to hold the sax in position with my right thumb. The weight distribution also feels much better with the strap beeing attached at both ends of the sax rather than the middle.I’ve been using the shoulder strap from my contoured case as a single shoulder strap for years.
There are also other companies making single shoulder straps out there.
I thin BG straps may have one also.