Psychokid, who posted the report on HST is a member here. Maybe he'll weigh in on your questions. I didn't think Discovery was anything to worry about. Actually the short section between the Whitney Main Trail and the ridge is pretty steep and tough to find anyplace to get a grip. But it's short, and you will find a way.
If you have done the Whitney MR, then you can do Crabtree Pass. The west side of Crabtree is probably the toughest, and it isn't as steep as the final 400 on Whitney.
I saw a report where the snow on the slope just above the upper Crabtree Lake caused hikers doing a traverse to have to climb above it, since a slip would have dropped them into the lake. So when going down, you might want to angle to the upper (NE) end of the lake. When you go down that slope (easy scree), try not to mess up any of the use trails -- they are tough climbing.
When I climbed from Sky-Blue to Crabtree, I veered west, and wandered around a bit, crossing the part between the two lakes, but I think you can stay to the east side of both lakes.
Below Sky-Blue, it's a walk in the park.
I dropped from upper Soldier Lk to the lower, and then climbed to the ridge, because I couldn't see a route around the nose of Major General, but I learned after the hike that it goes pretty easily.
