Well, I didn't spend a day in the mines, but I did venture out into burn country.
In order to get a true test of how the cross bike would feel on the DK I took it out on some of the tougher roads we will have to traverse. On your typical gravel roads the cross bike is a no brainer. It's light and fast. However, the question was could the bike, and more importantly my body, stand up to the abuse of your not so typical gravel roads. In fact, you can't even call them gravel. Dirt and rock is more appropriate. And you may be saying, "well that's what a gravel road is, dirt and rocks." But let me be clear, there is a big distinction between gravel and the rocks that inhabit some of these roads. To top it all off I started to roll into some smoke. Just a little at first, which maybe would have been enough to deter some from continuing. But not I. Call it perseverance or stupidity (I would go with the latter), but I forged on. And yep, there was more burning. Miles and miles of it. For a true challenge come try some of these hills while holding your breath. (on second thought, I don't recommend that) Don't worry, the burning will be done (I hope) come DK time.
Back to the point of this whole story, the cross bike felt fast on the climbs and surprisingly smooth on the descents (as smooth as these roads can be). Sure, it's going to beat you up a little more then your mtb, that's a given. And you might run a higher risk of flats. But, in the end I feel the trade off is plenty worth it. Of course, I enjoy a little time in the drops. So, if you're trying to decide mtb or cross bike, (as most of us are) I would highly suggest gettin' on the cross. I'm running Ritchey speedmax's, the tires make a big difference as well. Of course, I only did 45 miles yesterday. I could have a different opinion once a get a longer ride on it!