But seriously. Throughout the trip all the way to the last 150 miles or so (the hardest) a major worry was my knees.
So even with mild climbs as soon as I felt any perceptible strain on them I would drop a gear, and shamelessly ended up grannying up even some relatively mild (but long) gradients.
A strange thing happened; I actually began to enjoy going uphill. At 5mph you see stuff you miss at 12 or 15. Of course I wouldn't want to do the WHOLE thing at that speed, but when I had cause to, I enjoyed it. I'm a big bird guy too (I even get paid for it sometimes) and I made several good sightings at that speed and, more to the point, could hear more species by their calls.
First time I walked was about 50 yard stretch on 303 crossing the Cuyahoga Valley in Ohio. I could have pedaled it, and was, but I was straining so hard standing on the pedals to do so that it occurred to me I could pull something and be grounded for days at least, or worse, mess up a knee.
Later on in New York I was miffed that I was not actually enjoying hills anymore, whereas I would if I had a lower gear to resort to.
Again, others' MMV