As SRGTD said it will re-set automatically.
I know mine is
only the 230ps MK 7.5 and is a 6 speed DSG (which is thirstier than the new 7 speed unit), but I just checked my Fuelly account and got this (see below). I've had 3 MK7's now (2 GTD's and the GTI), and to be honest, the penalty hit in fuel isn't as bad as I thought it would be. Also note the best mpg of nearly 47mpg (real) for a journey to London late last year, and as you can see, the GTI can be both fun and frugal !
Added to that, 80% of my journeys are town commuting, I don't think this is too bad. Also, up until 2 fill ups ago, it was showing 36.5mpg, but the town I live and my route to work over the last month has been plagued by roadworks resulting in the last two tanks not being as good as they have been (circa 32-33mpg), whereas I usually a good 3-4 mpg higher.