Moral? In normal situations don't pull open descent at FL410 if you are descending into a tailwind / quickly weakening headwind.
Firstly when 100kts. head wind turns into 50kts. tail wind it is not normal. It is a serious wind shear and what happened is not unusual. It could have been worse as it could have tripped the auto pilot or triggered alpha protection. It has happened before. So open descent is not the cause. Secondly the original topic by MD80 was manually reducing the thrust quickly in open descent, which obviously one shouldn't and aircraft pitching down steeply to regain lost speed which it should. If the thrust is reduced as auto thrust does then there is no problem. My point is AB FBW may pitch down to whatever degrees but it will do so at 1G, you can call it a steep descent and want to avoid it, that is fine. Toulouse style protections is another mystery, may be he is repeating a phrase by one of his experienced Airbus sceptical instructors because by his own admission he is a neophyte to the bus.