DUG: Getting over Trail Crest with a big load is more than do-able. The trick? Slow and steady. In 2007 for my big trek my pack was 63 pounds at the trailhead, and I went all the way to Guitar that day. My friend Doug Forbes paced me to Lone Pine Lake, making sure I was keeping to about 1.5 miles/hour. On the switchers, I sat on a rock every 10 switchers (which contributed to my pants tearing on day 1!!), but that traverse to Trail Crest was the sweetest.
If I remember correctly, I left the trailhead just after 0400, and got to TC around noon, with a healthy hour break at Trail Camp to fuel/water up. You'll be sore the next day, and beware the rolling terrain between Guitar and Crabtree and then north on the JMT to Wallace Creek, Bighorn Plateau, and Tyndall Creek. Your legs will want there to be a bit more downhill than what is actually offered...
And if you need any sort of help at all, you know who to call.
