Also don't think this makes much sense at top level. Raiding is centered on getting gear to make stuff easier, both by making farm content quicker and by giving you more room for error where you progress. Also, progress raiders that chase through the top end instances aren't the only ones that like to gear their characters. If a player that is content with doing his weekly AK runs to gear in myth gear was hit by this (and I think we have a lot of those), it will mean he will never feel the effect of getting an upgrade, since power wise, he'll be stuck at the level of the green AK drops indefinitely.

On a related note, one way to not have CT "useless" and facerolled on release would have been to retune it to be the next step after coil after the developers realized they wouldn't be able to get it in for the launch. Sure many have suggested this, but guess it's a bit late now.