Yes, in running terms 16 is very doable, weather permitting, this year saw torrential rain, I wasn't there so only know this from others blogs, which left the course all but unrunnable for several hours. The challenge as your earlier post alludes to is more mental. Not sure I would run it in a pair; when I ran in 2012 I came across all manner of issues from one half being late to another just upping sticks and going home! There seems to be a few more of these on the calendar now with Joust 24 and Equinox 24 just two I can think of. Anyway I really enjoyed it as a race on its own and it was a perfect way, to safely see, if I fancied running one of the longer ultras point to point; when I did tackle the longer point to point the confidence I had in staying awake and runng through the night garnered at TR24 was most helpful.
Great event; I found I was just about bored when it turned dark and then enjoyed getting the headtorch on, when I was just about bored of running wth the headtorch the dawn broke with all the energy that brings. Solo runners are encouraged all the way around by relay runners, the route weaves in and out of the campsite so you get lots of cheers. I will certainly go back.