I can't remember any theologians formally attempting to correct JPII or BXVI.  There were plenty of theologians addressed by the CDF and over 100 placed under some form of silencing discipline, but that was for speculative works they published, not for direct corrections of either pope.  Hans Kung came close, but even in his case he was not 'correcting' papal teaching, but suggesting there were other ways to look at the teachings he disputed.