I consider the roadside portion of MPLR to be the hardest of any to fish on the TN side of the park. I contribute it to the quantity of fishermen it consistently sees on a daily basis. Dare I say, but I feel more hate for this section of water than love. I routinely drive right past it to fish other small streams in the area, and if I am really looking for some fantastic fishing I expect to put in at least 6 miles roundtrip hiking.
That being said, the headwaters above the parking area are some fantastic streams.
I have found that just a little bit of leg time, even 1/2 mile, will increase your fishing success.