Notes
Not positive distance was 20--may have been between 19.5 and 19.75, but I don't think that matters much since I got in a 5-hour run on trails and felt fine. Distance from car to trail head to trail is about .33 mile, then there's a bit of running before reaching trail itself, so maybe a little less than .5 total. Then trail is supposedly 3.75 miles, but Garmins at closer to 3.8. Conservatively, 5 laps at 3.75=18.75 + .8 from/to car=19.55, while 3.8X5 + 1.0 from/to car =20. Splitting the difference gives me about 19.75.
Used Polar, not Garmin, since I doubted G. would last the whole time. Tried to keep laps under an hour, mostly did.
Wore: C9 tights over UA shorts, Pearl Izumi jacket, don't remember shirt but probably one of the Drumstick Dash ones, red/black hat, regular glasses. Dropped a glove in the garage, but luckily had the red BR hat along--wrapped that around other hand. Took glove and hand-hat off after a couple of miles, but continued to hold them, which added warmth to hands but not too much.
Nutrition: This time ate every 30 minutes, slowed to a walk while doing so, tried to keep under 2 minute break. Not always successful at that, but a few times was able to start after 1:30, so may have averaged out. 4 gels, cheese sandwich (cut in quarters, ate 2 at a time), cookies (1 each break), must have been something else but I can't remember what since there would have been 9 breaks... It was hard to eat near end, will try to keep "real" food for early in race. But this worked better than earlier long runs, seemed to avoid energy crashes.
Felt pretty good. No trouble driving home, didn't feel particularly wiped out, no major aches or pains, legs felt fine next day.