5 hours chugging up and down the Trent today.
I stick to the speed limit except where the banks are reinforced (to prevent erosion) there are no fishermen, and there are no other boats nearby. This means that a couple of times I get a couple of hundred metres up on the plane, but for most of 5 hours I'm plodding politely.
I look out for fishing lines and I give them a wide berth and slow down. I even slow down for the chap moored/anchored above the weir in a Honwave, fishing.
Imagine then, my amusement when I was packing the boat away and the same Honwave went past flat out on the plane, p***ing off the anglers nearby. They even commented to me that he was a fisherman because his rods were visible.