Whilst i find it difficult to attribute some of the blame on the engineers involved that day, ( the biggest mistake, but not the only, was the pilots failure to follow their checklist) there is one thing i feel uneasy about.
The MEL stated the RAT heater,IF INOPERATIVE, may be isolated and deferred. The RAT heater WAS NOT inoperative , and, as an engineer that would have had me asking questions !
The MEL is a straigt forward document that , unfortunately , is open to abuse should you choose to mis-interperate it.
It is down to the engineers and crews personnel integrity not to abuse the MEL, regardless of commercial pressure. Management and operations can be easily baffled by some technical garb to buy you some time to go and look at the schematics. A further 15 minutes delay isnt going to change anyones day.