Brian
This issue has been covered many times before and in some detail.
You are correct in saying that the aircraft has been accepted by the FAA as meeting the requirements of FAR29 amdt 47. However the gearbox does not have 30 mins "run dry" capability.
It will not run for 30 minutes with NO oil.
We can be clever and play around with the words. However the facts are pretty simple, or at least I think they are
