My buddy and I always took his older (15 years) brother on yearly fishing trips; John was an adequate fly fisher but very driven, "flogging the water to a frothing boil". One day when the fishing was slow John hooked a big brown, played it to the boat, where it popped off. At the rear seat I snagged the remains of the leader and handed it to Kelly to tie on a new fly, telling John, "a clean cut, he must have cut you off on a tooth". Kelly had rigged John's rod, and seeing that tell-tale curl ratted himself out, "no, it was knot failure". Sometimes you just waste a perfectly good lie;)