Remember the intelligent Deatclaws that lived in the remains of Vault 13 in the NCR of FO2? If the Enclave made them with FEV in order to make them a more controllable killing machine, how come the D.C. Enclave of Raven Rock and Adams AFB didn't try it? I guess they thought the Deathclaw mind control helmet was a better idea. Come to think of it, the Enclave ended up purging all the intelligent Deathclaws because they saw them as a successful failure, they hated what the Enclave stood for and were looked upon as another mutation to be wiped out. R.I.P. Gorus, the scrappy little Deathclaw scholor who aided the Chosen One.
It was a scientist (which I promptly kill when I first met him to get the good ending thank to the patch and to get K-9) saw intelligent Deathclaws as a danger to the Enclave force. I don't think the other Enclave care at all unless that scientist told the rest of the Enclave about the experiment. Anyways, think about it; an intelligent creature that can swiftly kill any humans in mere seconds. With intelligent, they can use strategy and tactics in combat. That particular scientist know they are getting too smart to their liking, and thus, consider a danger to the Enclaves.
Why they did not recreate these guys? I assume along the line that the Chosen One did kill the the man who pretty much knows how to make these Deathclaw smart in the first place. That, or that man lives, purge the intelligent Deathclaws of Vault 13, and then Enclave (starting from the bottom) try to recreate that experiment again, and not "fail".