That winter we ran the Wild Oak Trail 50 Mile run near Harrisonburg, VA as a training run. The course was a couple of 25 mile loops: you'd go out all the way around back to the start, then reverse and run the 25 miles in the opposite direction from originally.
Well, around the middle of the first 25 mile loop the elevation ranged up to over 4,000' and, being February, there was substantial snow on the tops of the ridges. We called it "postholing" as you'd sink knee-deep into the snow with each step. Needless to say, the course ran pretty slow.
Shortly before the 25 mile turn-around point we were ascending one last climb that seemingly went on and on and on, false summit after false summit. Every time you thought you'd reached the top, the trail merely leveled for a moment then resumed its uphill orientation. Only you couldn't see that until you reached the tiny plateau.
Which gave rise to Gary's Theorem:
"Seeing daylight through the trees only tells you that you are probably approaching the first false summit."
By the way, Bill and I bailed at 25 miles. The thought of trudging back through that trail and doing the postholing again--this time after dark--held absolutely NO appeal to either of us. It was a smart move.