takata, thanks for your last answer. It brings me on to a more relevent point.
There is obviously going to be political mileage in the pitot tube situation.
Consider, the aircraft was on a stable cruising stage at a pressure setting (i.e.not altitude). The pitot tubes may or may not have been iced up but whatever the case this can
not have been the catalyst of the disaster as there would have been no obvious indication of this to crew or instruments as the difference pitot/static would have remained the same.
If the pitot heads were iced then they wouldn't have had any adverse effect until speed or FL changed.
In fact the information transmitted about differing pressures between l & r pitots give a very good indication that both were operational.