Summit day. Left camp 04:15AM. Summitted 12:40PM. Back to camp at 7:15 PM -- 15 hour day. Now snow above camp until about 6,500'. Then on firm snow up to Christmas Tree Col. No snow on the other side of the col, down to the glacial lake. Only a little snow traversing the glacial lake, but mostly on rocks until we got back on snow at about 7,200', crossed another set of rocks, and then roped up for the glacier at 7,800'. Slowed by lack of snow on talus and boulder slopes, but we followed a great line until we got to the summit ridge. The snow didn't go very high up the ridge, and we were supposed to get on the ridge crest itself. Where the snow met the ridge, it looked too steep. Instead we crossed to the south side onto a sandy ledge and tried to make a rising traverse. We should have gotten directly on the ridge crest -- it is so much better climbing and so much more direct with less exposure than the south slope. The south side of the ridge was too exposed and didn't provide good ways to get back up onto the ridge crest. We finally got back up to the crest, gradually curved rightward, found the false summit and looked across a notch to the true summit. It was easy to cross the notch and scramble the true summit.