We did a great ride with Glenn last year as DMD prep - both sides of Hamilton from Alum Rock, then up Sierra. It was only 60 miles or so but with 9,000 feet of climbing! http://app.strava.com/rides/405601 Super fun ride. (Glenn suggested adding Sierra).

I will probably plan to do that route again about 3 weeks to a month out from DMD. I will let you know when.

You might consider throwing in some of the brevets I mentioned as your long ride for the month. I love starting with the 200k in January - it is a super fun/easy course for an early 200k. The February one is a lot harder. And this year it snowed. Both times I have done DMD the 400k was the perfect last long ride for me. And oddly the 400k always took almost exactly the same amount of time, even though both DMDs/400ks took quite different amounts of time for me (three hours less last year than 2007). It's a weird correlation and I am interested to see if it holds again this year.

That would be a challenge to fit it all in with the tri training.