Yum Yum is a 5.3 that thinks it is a 5.6....or the other way around. However you put it, if you forget about that little bit of 5.6 climbing, it's really just a 5.3. Definitely the hardest 5.3 in the Gunks as far as I am concerned. I usually do P1 and 2 together, but yes the route goes up the flak thing to the right, then there is a step down and across into the left facing corner with little to no pro. PGish for sure. Combining these two puts you on the nice belay ledge about 150' up. Then a short rising traverse pitch up and left to the alcove ledge belay, and the short, airy last pitch.