John Nicholson brought up a good point at Simply -- domestic silver angels' bars are affected by light during the fry/juvenile stages. Other angel breeders will back this up. The amount of light you keep on the fry will sometimes impact how intense the bars develop. I'm starting to wonder if it's more environmental than anything else.
My big question is, can altums actually interbreed with other species of angelfish? Even with all the hobbyists who keep altums with domestic scalare, I've still never heard of reports that the altums spawned with scalare, so even a cross would be quite a feat.
At any rate, as skeptical as I've been, I have decided to try a half-dozen. Even if they aren't pure altum, they definitely are very different from pure scalare, and probably with the added bonus of being much healthier and stronger than wilds of the former.
IP Discus (the breeder of the fish) posted a bunch of pictures on the first page of this thread, including adults. The bars actually look pretty good to me, compared to the ones from previous pictures and video that were posted from other sources:
http://forum.simplydiscus.com/showthread.php?85280-Tony-Tan-Tank-Bred-Altums