The park service should definitely limit the number of people who are allowed to climb Half Dome per day - not only for safety reasons, but also for everyone’s enjoyment. The park service limits permits for backpacking in high density areas to lessen the impact of large groups of folks in a small area.

And the big question is: where are all these people peeing and pooping? A few years ago my husband and I hiked from Mammoth to Yosemite Valley along the JMT (in mid-September) and were disgusted by the smells of urine and the sight of used toilet paper and other disgusting trash behind every tree and corner the closer we got to the valley. In certain sections, it kind of smelled like hiking through a bad neighborhood in a city. A lot of people who hike on this trail seem to not be aware of LNT practices and just trash the area. Permitting would not only reduce the sheer volume of people, but also give rangers a chance to tell people that it’s not acceptable to leave toilet paper and other trash behind.