Hmmm, this route looks to be about 50 kilometers long with enough climbing to trim up your holiday-inflated Chubby Cheeks (~8000').

Red = out
Green = back
Blue = short cuts

Short cut from Arthurs Rock = Marathon(ish) (~7,000')
Short cut down Mill Creek = 22-23 miles (~5,500')

Ummm, feel free to print and use for future reference:

Chubby Cheeks 50k

Map splicing, dicing and arrowing by the multi-talented Mary Boyts.