More on the Motu Proprio
Given the series of concessions that have already been made to Catholic traditionalists, and the radical views and program of those to whom this pope has given his approval and endorsement in the past, it is difficult to believe that with Summorum pontificum a definitive compromise has been reached and the matter will end there. A more plausible understanding of the present moment is that it marks another step toward a goal that the vast majority of Catholics would not countenance if it were openly acknowledged-namely, the gradual dismantling of the liturgical reform in its entirety.
I mostly agree. Though I am not fond of slippery slope arguments, the trend lines here are undeniable. And the SSPX's explicit rejection of the paschal mystery's centrality to the Mass - and the implicit embracing of that view by reinstating the old mass - is especially troubling.