You chaps with GTD's not using the electric supplementary heater to boost your warm air on cold mornings? That comes on when you select a/c on.
Yes got that box ticked on the climate menu.Didn't even know what it did till you told me there!. 
Worth people checking out though.
Sadly my dealer is clueless. They didnt even know at the PDI if the screen had been fitted or how to turn it on! I am not sure what on earth the auto function is supposed to do though if the screen never comes on automatically. I will have to go direct to VW with the problem I guess.
Now i'm beginning to question my sanity!.With this supplementary heater thing,maybe it's that, that is helping my windscreen to de-ice.Maybe i have the same problem as yourself and others.
It would make sense.The heated screen not showing on the consumers list until switched on using the touchscreen.It does de-ice pretty quickly though so it's probably just my imagination.
Next move.Switch on maually then compare to time taken on auto.Then i'll know for sure.

When my car was in for it's first service in September they mentioned that there were a few non safety related recalls/software upgrades that they couldn't do because of 'an issue with our computer system'.'We will do them next time you're in'.

Maybe the screen is one of them.