Weight
This metric is especially applicable in the nymphing scene, because our flies are designed around fishing in a certain part of the water column, and in order to design and tie flies that fulfill that function, we should be very aware of the weight we incorporate into our flies. Heavy flies typically sink faster than light flies. Fly design and material use also strongly influence the sinking and fishing style of the pattern, but weight cannot be ignored as one of the primary influences in how our flies sink. Dry flies are unweighted, and they float. Big heavy nymphs are significantly weighted, and they sink. I don’t think we need to beat a dead horse here, as the idea of fly weight will be discussed further in other parts of this book, but the overarching idea here should be that the weight incorporated into our fly patterns is a valuable tool for the proficient tyer to use in order to drive the desired function of the fly.