Ace post, and nice to see the ride too. I tend to use toporoute.com and bikely.com for mapping now rather than gmap-pedometer. Much of your route coincides with what Mike and I used last year, though we were a bit madder in terms of distance than you two. We're a lot less fit this year and I think we're going to really feel the burn next week.
Tempted, but not feeling fit enough this year. I think claroscuro has put it in our diary for next year though. Plus we've just spent most of today attending a wedding and want to have a bit of a rest. Good luck though (not that i suspect you'll see this 'til after).