I sent this question to a well-placed and knowledgeable Catholic: "Has the primacy of conscience over doctrine always been a contention of the Catholic left (say, since Vatican II), or is it a new attempt by the Catholic left to implement their liberal agenda?" I'll let you know what he says, unless he binds me to confidentiality and, regardless, I won't be able to disclose his identity.
In my mind, I'm likening the efforts of Coccopalmerio and Co. to destroy doctrine in the name of conscience to Julian the Apostate's last gasp effort to turn back the tide on Christianity. Secular historians say he would've succeeded, if his life hadn't been cut short.
I found Coccopalmerio's emotional plea, incidentally, unsettling . . . maybe even disgusting in its intellectual disingenuousness. It's almost like he just wanted to wash wave and wave of emotion over the rock, hoping the waves would smooth away the edge of logic.