playing devils advocate the ONLY documentation a crew should use is the officially certified documentation supplied with the aircraft i.e the RFM, not sales brochures, press briefings or hearsay
Spoken like a true lawyer dangermouse
Unfortunately there are times when following the RFM will kill you, you make the best call you can on the day knowing that you will have to defend your actions if you survive. I'm reminded here of the early 76 Allison overspeed boxes. The FAA/manufacturer came out with an edict that if the engine was installed in a single it was to be disabled (mandatory) but in a twin it was to be serviceable and in use (mandatory). Bearing in mind that a false overspeed trip (of which there were more than a few) could result in an accident (rig take off) guess where most pilots put the circuit breakers (illegal).
I'd be surprised if *any* gearbox could run for more than a couple of minutes with no oil whatsoever
Have had two incidents whereby the MGB emptied itself, fortunately one was on downwind at home base on return from an offshore flight, and the other entailed a 15 minute flight to get somewhere "safe". The latter was done based on prior information from the manufacturers tech rep, not what was in the RFM. Do I recommend not following the RFM? Of course not, but it needs to be remembered it's your butt in the sling. Which ever way it turns out the Monday morning quarterbackers will get you in any event.