I've been very busy watching my Red Sox and have neglected to answer. 15 yrs. ago a friend and I skied Tuckerman's Ravine together and vowed to ski all the steepest runs in N. America before reaching 50, when we thought our legs would be gone. Have since changed jobs and lost touch with my friend but have learned a couple of things.
1. It is dumb to ski things in order to check them off a list.
2. Steepness (or more properly the intimidation due to it) is very subjective. It depends on exposure, how you feel that day, the conditions, the company, etc.
3. No matter what it says in a guidebook there is always something steeper, often off the map, unnamed and seldom skied, that is hairier than the stuff in the book. Virtually every major mountain in the west has something like this.
4. I'm 63 now and the legs are still good, just not for so many hours per day. The nerves are not as good. Lacking the right inspirational company, usually my son, I am likely to wimp out.
5. Never ski something near your limit if you think you might screw up. Come back another day when you and the mountain are right. The mountain will always be there. But if it never happens, so be it.
I have skied some steep stuff, but not the ones you mention. The Saudan Couloir (now Extreme Couloir) was almost totally whited out the day we looked at it. We could see only about 50 ft. and that 50 ft. looked wicked so we passed. National at Squaw, on the skier's right of the Palisades, had a long deep crack across it just below the lip. It was late Apr., 70 deg., and the crack was growing each time we went up the lift. We did ski Mainline and also traversed in just below the Palisades cliffs and skied there. The only time I've seen the Cirque runs at Snowbird was on my first trip west and my head just wasn't there yet. Probably the steepest runs I've skied were at Banff Lake Louise and Mt. Wash., NH. At LL my son and I did a number of chutes off the high poma, or maybe T-bar. They were marked by a gate and a sign, that said "avalanche terrain, occasionally open", It was open and there were a few tracks so we went in. After 100 ft. or so of moderate slope the bottom dropped out and we were looking at about 2000 vertical ft. that scared the bejeezus out of us. The snow seemed perfect. 6-12" of powder over a "chalky" hardpack that was not icy and held our edges very well. We kicked a few snowballs over the edge, watched, thought for a few minutes and then dropped in. It was perfect, even easy after the first 5 turns. What a high! These were chutes used for the Cdn. extreme ski championships and they have no names, except A - G (or thereabouts) and they increase in difficulty with the alphabet. We did B, C, D. At that point my legs were shot but John did E & F.
In May of 2003 I did one of the Great Gulf gullies on Mt. Washington, NH. Here is a link to a panorama of GG runs assembled in 2002 by one of the friends who was with me that day. http://ca.f1.pg.photos.yahoo.com/ph/switzer_crowley/detail?.dir=/b6c3&.dnm=152c.jpg
Here is a link to my story of that day,http://list.uvm.edu/cgi-bin/wa?A2=ind0305c&L=skivt-l&D=1&O=A&P=5463
Here is a pic, of the Airplane gully, taken by a guy in another party we met that day. http://www.biglines.com/photos_large.php?picid=28516
The run in the foreground with no tracks on it is JT's, a true 50 degree chute that is rarely skied. My son-in-law and a couple other young supremely confident guys skied it later. The other run is Airplane Gully. It looks steeper than it is because the view is looking at it from about 45 degrees to the side. It is at but not beyond 45 degrees in slope angle. Slopes always look steepest when viewed from straight on. They look true only when viewed from the side. You can see a skier with a white hat standing at the top of the rock tongue and 2 more on the snow at the top. There is one skier climbing in the extreme lower right corner. These are very serious slopes and people have died here.
The following day my brother-in-law and I skied the summit (east) snowfields, which are easily accessible to any solidly advanced skier. http://list.uvm.edu/cgi-bin/wa?A2=ind0305c&L=skivt-l&D=1&O=A&P=6622
The auto road opened on this weekend. Every year there is a period of 2-4 weeks after the auto road opens when you can drive up and avoid the long hard hike to access the mountain's skiing.