I've incorporated the option of doing the loop into my Denver-Durango 2014 thru hike - with the idea of keeping the Collegiate East half of the loop optional depending on how the trip is going when I get to the point where I have to decide.
I plan to mail a resupply box to Twin Lakes and from there I'll hike the Collegiate West route picking up a resupply at Monarch Crest Store. I would continue past Monarch Pass/highway 50 and meet the main CT route in Segment 15 and turn northbound at that junction returning to cross highway 50 and hitch into Poncha Springs/Salida, stay at the hostel and resupply. The next day, I would either hitch up 285/24 to Twin Lakes or arrange a paid shuttle (probably $$$). Then resume the CT southbound on the Collegiate East route with the supplies purchased in Salida. When I reach US 50 again on the Collegiate East, go back to Salida, resupply, and then continue on southbound, probably choosing the Monarch Pass trailhead and repeating a short segment of the Collegiate West since there would be less elevation gain vs. repeating the short segment of the Collegiate East.
If I don't feel up to doing the loop, I will retain the option of just continuing south when the Collegiate west rejoins the main trail in Segment 15. I would plan to put enough supplies in the Monarch Crest Store resupply box to get to Creede in case I choose this option. Since I won't be mailing any supplies to Salida and instead resupplying in town, there won't be any wasted resupply box if I decide to skip the loop.
This seems workable to me based on my research as well as the good information posted above - if anyone sees a major flaw in my thinking, please let me know! Thanks!