It's just a silly thesis, that's all.
It probably is but I remember in my lifetime (I'm 54) a similar strange series of deaths involving potential witnesses in another "Grand Conspiracy" about the assasination of JFK. The DA, Garrison, eventually threw in the towel as there were no witnesses left!
Of course, with the passage of time, we now know that Lee Harvey Oswald acted alone...don't we? :)