It's pretty evident that MIB is able to inhabit unburied dead bodies to mislead the current crop of Jacob invitees to his side of the backgammon board and effect the general outcome of island life. It is also evident that 1977 Dharma is aware that there is a problem, hence Amy's seemingly overplayed concern with the burial of the two others that killed Paul.
So what prior to 1977 taught the Dharma folk? Maybe we'll never know, but I theorize that MIB's hand is in the events of 1977. And by looking at their actions the people who seem to have the largest role in determining outcomes are Horace and Radzinsky, don't be too surprised if we find that one of these two died before we knew them. My personal bet is on Horace, as he built the cabin that eventually becomes MIB's prison, which seems too much a coincidence to me.
One other thought , is it possible that the truce onluy exists to limit the amount of bodies likely to be left laying around?
Look forward to your comments , Control