This is an emotional issue for a lot of people. Some get a bit carried away, calling other's J--- A-- and worse. Both sides get hot. That is why I try to throw a little humour on the fire (sometimes it helps...sometimes not.)
What got you into trouble was that recently there was a very hot arguement on the subject and a lot of people said a lot of very unpleasant things to the point where No one wanted to discuss it further. You had the misfortune of opening the door again.
But to the question: I agree that there is no way you can engineer a physiological change that extreme in a snake without seriously compromising the health, welfare and even identity of that species.
These snakes evolved their entire structure around the use of venom as a food procurement (and to a lesser degree digestive) function. While some more vigorous Elapids might adapt, it would be crippling at least to those who sacrificed muscular strength for their toxic ability. For Vipers, it would mean a life totaly on dead prey as they could not survive in the wild. A plus for keepers, but do you really want to cripple an animal like that?
When you add those factors, throw in the historicly careless nature of the pet trade, where many people out there who sell cannot even identify common snakes (trust me, I ID an amazing amount of snakes for dealers, including Indigos and Coral Snakes that were mis-IDed).
Picture the scenario: A guy walks into a shop and sells (what he says is...)a genetically altered Elapid. With no way to externally confirm this, the dealer turns around and sells it as a "G. Venomoid". Only it isn't.
Far fetched? Think about it.....
Some things are just not worth trying.
Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."