Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
John,
I'm sure if you spoke with Jim, he'd tell you that dubbing as Leisenring did is not quite the same as dubbing in a dubbing loop. The results are slightly different.
Mark
Vern also tied his flymphs on up-eye hooks. He said they looked better when drawing them up through the water column.