When I was a little guy, I would always marvel at those blenders.
My Grandmother had a Chrome Based Waring Blendor with two speeds.
When I got older the first time I had an encounter with a 39 Speed Blendor, when I ran it though all the speeds I found there was little difference between all those speeds. So really it was just a few more RPMs or Less than High or Low. And if you're blending something, You want it blended. Yes this was pre Food Processor, but I hardly found a use for the Blendor besides Pureeing, making Bread Crumbs or back then... Frozen Daiquiris.