If I'm reading case d correctly, if 3 generations are in play at the end of the taxes, the oldest generation is removed from the board, dice and cards. The next generation has all of its dice restored to the max. Why would the 2nd generation get its dice back?
It would have lost one when the 3rd generation got started.
Why? The only thing that can happen when you start a new generation is removal of remaining buyable factories for the now-obsolete 2-generations-back-of-same type, activating initial orders, and rolling an initial order for the next, newly available loco type.
I find it counter intuitive that more demand would come back just because an older model went obsolete.
Am I reading the rules correctly?
It's a way of putting a little brake on the train rush and avoiding the situation where the slow ramp-up for a model wasn't fast enough to fully populate it before the leading edge moved on. If you like, it's the model benfiting from people who would have bought the now completely obsolete older model.