So you've raised ONE chameleon to adult size (what, 8-12 months?) on canned insects and don't have any signs of issues yet?
That's not quite enough info to make the statement that you can keep healthy chameleons their entire life-time on canned, un-gutloaded food. Especially since we have to assume you're right when you say that he's healthy, has no deficiencies, etc. (and that's not personal, but we have people all the time that say "my chameleon is in great shape, I don't know why he's suddenly on the floor!" and then the photo shows a totally deformed chameleon that hasn't seen calcium a day in it's life. So we take people's claims with a grain of salt!)
Sorry to be the skeptic but those feeder insects by themselves have fairly terrible ratios of things like phosphorous to calcium (some more than others) and without any gut loading make pretty poor food. You can correct for calcium with supplements but they're void of any additional value. If anything, it says more about the hardiness of veileds more than it does about the quality of nutrition! I'm sorry, but I wouldn't recommend this type of diet to anyone, ever.
I went to the Vet yesterday and she said that "Your chameleon is as healthy as can be, you must be doing something right" I asked if he had any deficiency and she said not the slightest case of MBD or anything I can tell. His bones are completely straight and have a good high density. So I have told mt fried Trevor to try an all Can O' Dead Food Products. Ill post an additional link on how that turns out in about 2-3 weeks.