I've been racing all day on DR Gardens. I'm actually starting to enjoy the track, it just needed some brute force experience. My DR graph however, looks like DR reset. I've driven all the GR.4 cars, never used the same car in a row, sort of random order to keep it interesting. Actually I did use the Ferrari twice in a row as it still had heavy wet tires on from my stunt driving on Tokyo

1:47 best lap with heavy wets while trying to get the pit crew to provide service. They ignored me, bastards were having lunch.
Lap 1 to quickly figure out how the car handles then try to get in the rhythm by lap 3 and pass some cars. It's not a good strategy to get fast at all, just having fun. My best finish so far was 6th in the Lexus and I did once get the fastest lap in the GT-R. I'm down to 15K DR currently, still getting matched with the 1:38 crowd on pole.
The backfield is 'interesting' in the gardens, so many places to stick a nose in to bump pass. The game upped the ante as well, giving me a standing start in one of my races. Just sitting there all by myself waiting for the timer, auto drive not working. Sure give everyone a 10 sec head start as well...
Now if only I had written down my best lap times with each car so I would know which ones to try more... Oh well. I wish it had a random option for the car. Half the time I had already forgotten which car I picked when the race started, can't find out either until the finish in bumper cam. Driving unknown, fun.