You’ll need:
 Basic Route Finding – 8 tenths of the route is just following the north fork of lone pine creek. I think it would be hard to actually get lost, however good route finding skills (and doing your homework) will save you a lot of time and frustration.
 Snow Travel Skills – This becomes less important as we head toward summer but basic ice ax (self arrest), crampon, and glissading skills are required for snow travel.
 Rock Climbing – It’s easy to get off-route and find yourself needing some decent rock climbing skills. If you have a good guide to show you the route technical climbing skills shouldn't be required, but you’ll be much more comfortable in some of the third class scrambles if you have them.
 Fitness – this route is much more physically and mentally demanding then the mail trail.
 Permit – For an overnighter permits (on the quota system) are required - for day trips you still need a permit to travel in the John Muir Wilderness but there is no quota. And you may return via the main trail. Or at least that’s what I was told two weeks ago in the Lone Pine ranger station.
If you don’t have good basic mountaineering skills don’t try it on your own.
I prefer snow travel to rock and scree, which makes spring the best season for me. Winter travel would require avalanche awareness skills and summer travel in scree and rock would make the MR more physically demanding.
BJ