re: switchbacks.
The trail designers, such as they were back in the day, were true masochists. Literally direct lines straight up a ridge or alongside a gully. Given that they are on the fall line, the trails become rivers during rains. Unbelievably painful to hike.
No Forest Service namby pamby shallow grades and switchbacks here! Typical: the Air Line trail, ~4500 feet up at a 21% average grade.