Phats not being glitchable has nothing to do with the key block, well not directly anyway (obviously still need it to make image).
14717 blocked key retrieval on both phat and slim. Far as I know there was no leak. Another group of people released an update to allow 14717 and above to grab the key on the slim. TX then released theirs and had their usual little dig at other people, saying it was easily patchable and shouldn't have been released yet.
Phat had something done to the CB in the update, I'm not sure exactly what, but it blocks the old way of glitching them. Even if you have your cpu key, you can't glitch them. TX is working on RGH2, which will work on them, but will require new programming on the cpld and and different wiring.