I just finished a 60 mile section from Clingman's Dome south to NOC. In the past, I have never had a problem with any knee pain/discomfort with downhill sections. However about halfway through this trip, I began experiencing some discomfort in my knees. It is directly behind the knee cap, and does not occur when I step down (on impact), but instead is felt after the step, as the knee is being bent (descending). Oddly, this is only on steep uneven downhills. Anytime I as able to stretch out my leg and take a long, regular strides (even during steep descents), it faded away and after a dozen of these long steps was gone.
Not having ever had any knee problems, I was hoping others here could share any related experience. Thanks.