IB to S.Group - via "exceptional circumstances"

I was recently moved from long-term IB (15+ years, declared "Exempt" each time) to Cont-Based ESA (limited capability for WRA). I want to question the decision. I read somewhere (a BW pdf?) that a person deemed a risk to himself or others by being placed in WRAG should be put in S.Group-regardless of any other non-M.Health descriptors. My med report-which I wasn't required to attend-states: "Overall evidence does not suggest the S.G, however he would satisfy the threshold with combination of M.H descriptors". Sorry, but I'm confused, because the BW pdf (understanding_ESA_newtest.pdf page27) says "Are you covered by the limited capability for work-related activity exceptional circumstances rules? Finally, some people who are not exempt and to whom none of the limited capability for work related-activity descriptors apply are still eligible for the support group. This is because the exceptional circumstances rule applies to them. You will be treated as having limited capability for work-related activities if: you suffer from some specific disease or bodily or mental disablement and, by reasons of such disease or disablement, there would be a substantial risk to the mental or physical health of any person if you were found *** NOT *** to have limited capability for work-related activity .". Please can someone direct me to the ESA Regs, where this clause(s) is stated, or explain if I am making the wrong assumptions entirely. Further, why might the D.Maker decide contrary to ATOS' seemingly unequivocal statement (eligibility for S.G)? Also, is there any advice on how NOT! 2 get myself "sanctioned" as a result of a "work-focused" interview?