I've been OCD on metrics since I started in my teens, and kept logs. The main purpose was to learn, so that I could figure out what flies worked better on a given stretch on a given time of year. Later, this helped deciphering waters new to me.
Several decades ago, I started using a tape recorder on stream, and I'm still puzzled that I've never seen anybody else doing that although lots of anglers keep written logs (even on stream, which uses up ffishing time). I never got around to taking photos or videos on stream, which I now see quite a bit with the easy to use phones.
Being on the water at all makes the experience great. Seeing trouts, and especially rising and bugs makes it better yet. I like to see a landed rate of 5 trouts an hour, but it depends on conditions and especially trouts size. I went through a period of seeing if I could land 2000 trouts a year, and to that end distilled my approach targeting streams that had the capability of delivering 20-40 trouts an hour,
First and foremost, I had to figure out flies that would sustain several dozen trouts before having to change, thereby wasting ffishing time. I still don't consider a pattern as a general standard unless it tolerates 2 dozen trouts before needing replacement. The other point when going for the max count is to take a lesson from the English match fishing tournaments. To get to the 30-40 landed trouts per hour rate, necessarily I'm dealing with small, often tiny trouts. Under these conditions, my hands never get dry. When faced with seriously large trouts, say 18" plus, the logistics of playing them keeps me from expecting more than several an hour.
I need to check my spreadsheets, but I vividly remember getting from 40 trouts a session to 80 to 120. Somewhere after I got several 120-140s, my interests changed, since I began thinking about the mortality (maybe 1%) and wanting to not spoil the ffishing for the anglers behind me.
Now I still keep assiduous records, but if I manage 5-7/hr, I start playing with new fly patterns and messing with weird hooks (to see which ones don't hold trouts well).
Actually, now the trouts that interest me the most are the ones I don't catch, yet are still feeding away.
tl
les