I concur with EPS. After reading the EA two things stand out for me.
1) The EA does not make the case for an actual problem with the current 400 quota. Some congestion on the cables at peak times is to be expected. Go early or late or mid week if you want to avoid that. We were there last July around 7am Friday and had it almost to ourselves.
2) The EA does not explain how they came up with the estimates for people on the cables with a quota of 300 vs 400 permits. Table ES-1 has numbers that seem odd to me and they are not backup in the report. Am I missing something or is this all based on consultant estimates carried out to a false sense of accuracy? I just don't think there would be much noticeable difference in "crowding" with 25% fewer permits.
It's a popular hike and nobody should expect a true "wilderness experience" on this trail. HD lures a lot of people to get "out there" for the first time. That's a good thing in my mind. Some restrictions seem unavoidable, but keep them minimal.
I'm two cents lighter but I feel better now...
