Explain the Underestimation (undercounting) of the Messianic and the Absence Traditions in the "Basaer od Darajat"

Mohammed bin Hassan Saffar in his book entitled "Basaer od Darajat", which is the only book remained of his writings, cites just a very small number of account of tradition related to the issue of Absence. This is surprising since the central axis of the work revolves around the religious leaders in Ahl ul Bayt f the Prophet called Imams and their activities. However, the Ahl ul Bayt. Some researchers have suggested hypotheses to explain this phenomenon. One hypothesis is religious reservation. The other is that Saffar was not authorized by the authorities to cite these particular traditions and still the other pertains to the possibility that Mahdism related traditions were not developed at the time of his life. Some have been raised the possibility could have been his personal belief that Saffar may have considered the succession to Mohammad can begin again. The study of historical sources, figures, lists and other Hadith shows that neither of these assumptions can be true, since Saffar has had other works in this regard in those such Mahdism Hadith are quoted in them. The sheer volume of related Hadith narrated in his subsequent narrative works, are among the pieces of evidence in support of this latter claim.