Again, I would suggest that anything not easily worked out for oneself is automatically somewhat irrelevant.
No offence, but who gives a monkeys that each different key remembers the respective driver's climate settings?
You're the only person I know where you/your wife even use different keys!
Everyone I've ever known just uses the one key.
After all, if they're not driving the car, they don't need a key for it!
IMO, these are clever little things for cleverness's sake.
If 99% of people never know it's there, it isn't needed.
Indeed, as a side argument, dual zone climate, in itself, is largely irrelevant.
Can't agree on the same temperature in an 8' x 5' car?
Must cause arguments in one's mono-zone living room then...
I agree with you to a degree about dual zone air-con but it does mean my wife can have warm air coming out of her side vent and I can have cooler air from mine, but the overall temperature will not be effected.
As for keys, my wife always keeps her key to the A3 in her hand-bag. In the past with a much older Audi I have been in the situation where I lost my key whilst we were a long way from home. No problem, Jenny had her key in her bag. It just depends how organised a person you are. We always take both keys whenever we go out. Several of our friends do the same, so I'm certainly not the only one.
If you don't want to know all there is to know about you car then don't bother to read the manuals. If you car is important to you and like me you want to know all about it, then the manual is the place to go. Some people spent every evening watching television. Personally I cannot think of anything worse. As I said, each to his own.
