I've seen two references (one by Bob Burd) about an unnamed route up North Pal from the west side U Notch. It starts about 100 feet from the Notch and has been rated at 4th class. The LeConte route is further down the chute at about 300 feet from the Notch. Does anyone have any experience with or a description of this "mystery" route?

Moore variation

This one?

Yes, its the Clyde Variation! Thanks so much Bob. This is great beta. We plan to ascend North Pal via this route then rap into the Notch. We will then ascend Polemonium from the Notch and bivy on the ridge over to Sill (I was there last year and saw several bivy sites). Next day we'll summit Sill and rap back to the Notch. Anyone have an idea how cold it may get on the ridge at night?