Nonsense. The OP sets up a straw man just to knock it down. The descriptions of recommendation engines are naive, uninformed, narrow, and not at all comprehen

Nonsense. The OP sets up a straw man just to knock it down. The descriptions of recommendation engines are naive, uninformed, narrow, and not at all comprehensive. What can be done with good applied math for making recommendations has variety nearly beyond belief; the approaches outlined by the OP are, of course, just silly. For the cold start problem, that need not be very difficult -- just start in niches.