On a through-hike, the longer you go, the more you feel the weight of everything in a pack (and what you are carrying). Someone once told me if they didnt use it everyday, then they shipped it back home. Im not saying trekking poles are a bad idea, but there are many times, especially on rocky surfaces or steep inclines, that trekking poles clog up your hands and leave you vulnerable for falls and injury. So during these instances, you either have to keep em in hand, shorten em and put both in one hand (leaving only one free), or pack em on ur pack. Either way, i found it annoying to do any of the three on a given day, so i packed em up! Just trying to give you some perspective on the other side of the coin.
Aphex