I fished Crane on Fathers Day morning for about 3 hours. I had good luck below the city park. I used 2 lb. P-Line and a two fly rig under an indicator. I caught fish on each fly that I tied on, but the dropper outfished the other fly 3 to 1. I usually have a weightless fly like a hares ear nymph or PT nymph under a zebra midge or some other weighted fly. I tie several different buggy looking tungsten beadhead midges that work very well at Crane. I found that stealth is the key for the bigger fish and long casts will help with that. As wild as Crane is a long cast is somewhat relative, but still a good thing to remember. I too had a few refusals, but chalked that up to the fish seeing me, since they would follow the fly for a long time and then just disappear into the deeper water never to be seen again.
As Gavin said, if you don't catch a fish or you catch a few and they shut off just move up to the next hole and try it again.