One of the most dramatic changes has been in modern day showa. Initially in my classes I would have tosai showa taken out in the sunlight to catch the red at the tailstop under the black. This seeing is believeing method helped students understand what was going on....until more and more kohaku genes were used to strengthen the red and now I'm seeing less and less of the "false" sumi in tosai. Fortunately for Shiro's we don't have to endure the beni concerns
But is fun to see what happens in the pecs as well. Good post MIKe!