Actually, having done both in hiking the entire trail, I can tell you that hiking up and down Katahdin is just as legitimate or traditional as hiking up the approach trail. Almost all NOBO thrus have to do it unless they choose to go over the Knife's Edge and hike down (I don't remember the name of the other campground). But getting a hitch out of there is a bit more challenging than KSC. Plus, it's a butt kicker on the way up and on the way back down so you'll get the authentic experience Either way, enjoy it! And you are wise to take it easy in the beginning. Trail legs take a while to develop and pushing it to hard in the beginning can cause injuries that can knock a hiker off the trail for the season. Whatever you decide, I'm sure you'll have a great time.