Shin,
First of all, you post from yesterday got lost due to a server crash. The site has been restored, but the messages from yesterday were lost. I apologize. We'll be moving the site to a more reliable hosting service ASAP.
But trying to comment on your last (missing) post, I recall you wanted to backpack and camp in the Mountaineers Route (MR) somewhere, and then hike to the summit, returning by the Main Trail, and then re-climb back to your MR campsite and spend a second night.
Looking at it a different way,m you are combining two trips: A day hike going up the MR returning on the Main Trail, plus camping on the MR. (And please note, the North Fork / Mountaineers Route is NOT a trail, even though they permit it as if it is.)
You can do your loop hike, it just takes a different permit: You need the North Fork (Mountaineers Route) permit in order to backpack and camp in the MR area. And you need the Trail Crest exit permit to descend via the Main Trail. You can get both of these on a walk-in basis the day before you start the hike; just be there at 11 AM and hope to be first in line. (actually you draw numbers from a hat)
Your North Fork permit allows you to camp in the MR for up to 14 consecutive nights. Your permit is good, even if you exit at the Portal for less than 24 hours and return to your camp site. (So I guess by that rule, you could even exit the Portal and spend a night someplace else as long as you get back on the trail within 24 hours.)
I hope this answers your question a bit more.
