First a comment to RG: we climbed adjacent to one another one day this fall. You were on Alphonse as I recall. What was obvious from the way you moved up was the relaxed fluidity that speaks to years of experience. Lingering effects of your knee operation were not outwardly visible.
Yes, Frank, I remember. I think you were on Grand Central. That day was the first day I tested out my repaired knee leading 5.8ish climbs (Te Dum, Alphonse, Yellow Belly), the previous three outdoor climbing days having been devoted to leading climbs 5.5 and under. Although I don't know about fluid, you can get away with technique, which doesn't go away, on many routes 5.8 and under. But starting around 5.9 in the Gunks, hand-endurance comes into play on most routes, even if your technique is good, and that is where the seven-month layoff has affected me the most.