I have fished a few in my time. it took me a while to work out that the most fish are not in the fast water but some way downstream of it At least that is often how I have found it. I remember reading about float fishing silk weed in weirs for roach and that caught my imagination as a boy; you know those lovely old books with pen and ink diagrams of big cork floats and wooden rods. I still use big cork floats, my latest has not much paint left on it but it still looks good to my mind and I am sure fish prefer a damaged Rembrandt than a bit of graffiti.
Always attracted to weirs, the trouble is so is everyone else. maybe that's why I started fishing downstream of them to find a quiet spot and caught some good fish. I try the turbulent water but if not much happening take a stroll down stream and find some nice glides, the water is still oxygenated and fish are still attracted to it but happier to sit in a steadier flow and pick up bits of food; sometimes quite a long way back. I have picked up some cracking fish this way. Anything really, Barbel, Roach, Bream etc.