I'm with you, justme.
I am basically getting uneasy about posts like 777fly's, bubbers and others with suggestions that those involved (the crew and engineer) should have 'correctly diagnosed' the problem. (Leaving ?possibly? AB aside), an aeroplane - if correctly set up - will fly without any of these 'failsafes'. I just cannot see how blame can be attached to these poor folk for not understanding a complex logic system of switches and relays. The MEL system NEEDS to have been constructed with all this done in advance, surely? Certainly the limited tech info available to me in my seat on the ramp would in no way have allowed me to follow all the relay switching involved nor to be CERTAIN there was no other failure in the system that could heat the RAT sensor - and it really is not the pilots' job to do so either. The logical progression here is for me to insist on full access to maintenance manuals before I accept a signed off defect. NO - I am trusted to fly the a/c properly and I trust the engineers to fix it likewise.