Goodman, David, "Backcountry Skiing Adventures, Classic Ski and Snowboard Tours in Maine and New Hampshire", Applachian Mountain Club Books, Boston, MA, 1999, ISBN 1-878239-64-3. $14.95.
Available at the usual outdoor gear stores.
Actually, it was more of a lollipop than a loop.
Hardcore? Hardly. Just persistent...
25 miles in 17.5 hrs is hardly breaking any records.
It was, however, solo on a Tuesday. Didn't see anyone else for the entire ski.
The real hard part was the drive home...
I had previously skied all except for the TFT, the southern part of the SPT, and a bit of the Wilderness trail near Stillwater. Helps to be on largely known territory... My original plan had been to ski up and down the SPT, but conditions were so good that I decided to do the TFT, EPT, SPT loop. There were several steep downhills on the "up, over, and down"s on the TFT which I walked--not good places to risk a screw-up.
Yes, the river crossings are real, and if you back off, your only choices are to turn around or find another route. The route follows the hiking trails and the crossings are described pretty well in the White Mtn Guide.
D.