Crab - you are quite right, as far as I am aware nothing has been confirmed, but it is still a plausible explanation.
FH1100,
So claiming that moving the driveshaft to the rear of the pylon is a "safety" feature is...well...arguable I think.
Personally I think the rationale is sound, but of course everything is arguable, and this thread would be rather boring and pointless if we all agreed on everything all the time!