Having the discount for Day Travelcards would of course be great,
however so long as the discount is only available to zones 1-6 Day

I've certainly had the GOLDC discount issued on Z1-4 travelcards from an NR
station in the past, physically it's possible but I guess it's not a
permitted product (though the kit certainly allows its issue).

I see what you're saying, it would complicate matters to allow it.

Hopefully when some form of integrated smartcard ticketing comes around
this won't be a problem anymore (though I suppose discounted tickets will
always need to be done on paper or loaded specially onto the card?).

Cheers,
Dave