To any aspiring thru-hiker that wants to carry a solar charger on the AT, I say go for it, recognizing however that I've never seen any reports from any that carried it all the way and recommended that approach for others. I admit that my own (PCT-based) solar experience was based on not-current technology, for what that's worth (I used the Solio available in 2008). I'd point out that it's not just the green tunnel effect, but also the "walking most of the day" effect. I.e., don't test in a stationary location and expect to get the same charge as having the thing mounted in some way on your pack.
Please DO report your personal results here afterwards. If at some point someone does a thru-hike, on the AT, carrying a solar charger all the way, and shortly AFTER finishing their trip they recommend that approach to others --- that's the time I might start considering it.