(12 Sep 2016, 9:08 pm)Adrian wrote I'm unsure if that'd work. We previously had the 183, which was arguably quicker than the route you've described to the Metrocentre, and that was withdrawn due to low usage.
Harlow Green/Allerdene is an interesting one. Parts of it are, I'd say, in reasonable walking distance of the Loop. That will get you to/from Team Valley, and you've also got the Coaster and Angel connections too. Parts of it are perhaps not, but a more likely solution would be to adjust the Loop route.
Looking at reasonable routes on a map, I really don't think there is one that will work from Washington, which is probably why it doesn't exist. Your best bet would probably be routing the Red Arrows away from Old Durham Road, but that would not go down well with existing customers, due to increased journey times.
Looking at Andreos1's idea, you could extend the 85/86 from Concord via Springwell and Harlow Green to Team Valley & MetroCentre.