Blocking stutter and selective mutism should be classified as an invisible disability because people who don't know just try to explain away by assuming things like shyness, forgetfulness, anxiety, unpreparedness or silent treatment. Now I tell people "I have a speech impairment and I like speaking". By saying I have a speech impairment instead of stutter, I don't have to deal with misconceptions about stutter that people have. By saying I like speaking, I don't have to deal with misguided kindness of not letting me speak. Show people youtube clip of Amanda Mammana on America's Got Talent or John Hendrickson's interview on MSNBC. Their stories will convince them speech impairment is a big deal, I hope.