I have had a few interesting catches using large flies. I have a particular Pike fly thats is fluro orange and yellow, some 6-8 inches long and dressed to look like a big goldfish. I have had around 10 Rainbows on this, all in the 2-3 pound class. I had a sub 1lb rainbow hit a surface frog pattern that was around 5 inches and a Brownie of around 2 pounds on a black bunny dressed on a 5/0!!!
All these fish came from waters where trout anglers regularly fish tiny buzzers, spiders etc.
I have also had a few big brownies on 2" minnow patterns when "matching the hatch" after seeing fry scatter and thinking it was Pike or Perch.
Trout are not put off by 50 lb Titanium single strand wire by the way