I will say that my Ti experienced this on part of my trip to AL the other weekend, though I believe that it was a result of the road surface. It felt the same as riding a motorcycle over the wavy-grooved roads that occur when the road crews are prepping for re-paving.
It was only on one section of the interstate, for however many miles. I also experience it on roads that have deep tire grooves from wear. I forget what they're called. But I attribute that to the width of tire...it's definitely a rare occurrence for me and not across all types of driving situations.
FocusFest 2013: Best of Show
Gateway FFW: Show Class Outstanding
September '13 ROTM