I tried this idea with a bunch of my leopard geckos.... I mean if I could get them to take frozen thawed pinkies out of my hand, why not other stuff? But these were animals used to being hand/hemostat fed, so they kinda figured out anything i was holding had to be food, and the ones that got like this ate anything (bad news for my fingers). I've also had a treefrog and some toads do the same thing, or at least ate twirled crickets out of my hand. Those jumble bowls scared the crap out of any animal they were tried with. Once the animal put one limb on it they never went near it again. They are one of the stupid reptile products catered to bug-haters and no one should by along with the freeze-dried bugs (which aren't that great for your critters anyways).
The problem is that dart frogs don't eat out of your hand, and the thing has to be moving. Other than some of the phyllobates and maybe an epipedobates or something (meat on a string... it worked for leopard frogs...) but other than that, I don't see it happening. For most lizards and amphibians, live foods is the neccessary evil and part of keeping them as a 'pet'.
