A few guys described a strange situation years ago for some very highly-experienced US pilots who went to work for ANA.
Some of them had retired a bit early from TWA, and had flown airline jets for about 30 years. They sat through at least 6 months of groundschool. Some had retired on the 747 at TWA or NWA. Their training was so deep in theory (even radio wave theory), that they were considered to be brand-new novices in aviation. On one day, they reportedly spent a whole day "learning" to move the slat/flap handle back and forth.
Since hearing some of these stories, however true or accurate, I've always wondered whether such an approach to training reflects what pilots need to know or whether much of it was some sort of indoctrination into a religion, mostly disconnected from actual aviation-maybe Zen archery?