I found this piece by Loren Williams interesting with re to why Czech nymphing was the norm for grayling. With the destruction of mayfly populations, the fly fisher adapted to the remaining caddis populations and the resultant heavy dredging of the beautiful Cz/Pol nymphs. However, the competitive fly fishing venues necessitates fishing to the circumstances or conditions and Williams noted that Czech Nymphing is not always successful where mayflies still exist….hence the micro nymphs that many of us in the West take for granted on certain waters. Size 14 and 16 (smaller if you have the patience to tie and fish) seem the norm for our mayfly matching. Still interesting on the adaptability of competitive anglers. The techniques of East/SE Euro’s, Italians, French and Spaniards is definitely worth additional research in order to see if tricks are to be learned to expand the arsenal. Sometimes, I think we do these techniques in a half assed manner and they work…we just intuitively play around til something works… Others think through these processes and figure out the why’s. Perhaps the difference between recreational and competitive fly fishers.