I do not think this is something that can be taught by humans. But do snakes eat frozen/thawed without injecting any venom? Well i Have seen them take dead rats layed in the cage without striking them, though they could be injecting venom while walking them in. But I would even be willing to bet that in some cases CB snakes might actually stike and eat without venom injection.

However I do not know of any research on this one way or the other and am only speculating
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Dan S.
Crotalus & Company
Venom-Center Your Complete Venomous Community
Wisconsin Reptile Community