Even the original 5.3 miles of "Old School" trails of Dark Mountain, seemingly always has an eye towards flow, it has bigger climbs, grade reversals and sharp hairpins. It is just more rugged!
Be sure to ride trail #8 down to the bridge down river from the dam. Even if you may have to climb back up, it's a good climb too! #8 is my favorite descent in the system., old school feel with sharp hairpins.
OVT is bermorific, this part of the system cranks up the flow a notch. Usually done as an out and back, often in between Dark Mountain and Warrior Creek. I have been working on keeping my weight centered and I am coming out of turns faster than ever before making sections of the trail seem endless. Take the Berry Loop on the way towards Warrior Creek an Shiners Run on the way back, they flow nicely that way. Making the most of the elevation change, Berry Loop (1.5 miles) gets even more swoopy and even some of the berms going uphill seem to conserve your momentum. Trail boss Jim Horton was working on the second half of Berry that will eventually form a figure 8 with OVT. Shiner's Run (2.3 miles) uses noticeable elevation change as well, but is more like original flavor OVT in the flow department.
Warrior Creek is a super sweet 11 mile single track loop. Berm after berm of flow, begging you to stay off the brakes and maintain every last Newton meter of momentum for the next grade, direction reversal or the occasional obstacle or feature. It was literally an endurance workout for your flow skills.
I rode for a bit of OVT with Mike the Owner of Magic Cycles over in Boone while was testing a 650b Giant. Pretty nice guy.
Here is video to get you started. I will add a few more.