I was there for a week in 2007- hired Early Winters to pack us in. Decent packer but nothing fancy. We packed out of the bowl just past harts pass - there were a ton of cars at the trailhead and on up the other side where they kept the stock, and further up the ridge where the DIY's park. Probably 20-30 cars total. We camped on the main trail head in the valley 6 miles or so in, and ran into people everywhere - hunters, hikers, etc. on every trail, and every ridge.
We saw two shooter bucks down lower on our drive up to the pass from Mazama- we were stoked.
However those two bucks were running a ridge going out of the wilderness area.... and the last legal deer we saw. After 2 hard days and thousands of feet of vert, we stopped hunting for deer and just tried to find sign of any kind. It was scarce to non-existent. We scoured the area. Then it snowed and we thought we were in like flynn... hunted 3 days in the snow- again, up and down the ridges, rock slides, in the timber, etc... still- hardly any sign... did see cat tracks though.
I truly believe the population is thin- at least any area that is within a day or two's hike from Harts pass, or frequented by the outfitters. I think they had in 10+ camps. That is a lot of traffic.
Here is some good data - check out early winters hunting picks - only 1 buck from thier high hunt drop camps. The rest are from General season.
http://www.earlywintersoutfitting.com/home.html