I thought this was really to give operators the ability to say it's OK, and remove most of the liability from them, as well as the "buddy". Some operators have been doing their "own" certification of sorts.
Mike Ball Dive Expeditions in Queensland and Papua New Guinea has been offering solo diving for their guests.
When you board Mike Balls dive boat, you may request solo diving, and if you meet the pre-requesites, you may dive at your leisure, all on your own. To participate in their Safe Solo Diving program, you must be a Divemaster over the age of 18 years, or be over 21 years of age with proof of 100 dives. You must have a redundant air system, a Dive Alert air horn ar similar signalling device, knife and compass. You will also be subject to a skills evaluation before you will be permitted to proceed.
Frankly I'm for it. No one should cry about a SOLO diver, and no one has to be responsible. This is a very individual choice. Precious few of those left anymore. This should put much more emphasis on whether the instructor felt the student was really ready, before signing off on the cert.
And as an operator, aren't they still free to refuse service? Like Mike Ball's outfit, just because you have a SOLO cert doesn't mean you'll be diving SOLO with them. Individual operators choice still counts, I hope.