Whoof — this brought back memories of endlessly typing things like...

kkk kik kik k,k k,k jjj juj juj jmj jmj hhh hyh hyh hnh hnh

...on a lovely, bangy, ink-scented IBM Selectric in typing class. Which at the time felt like a meaningless exercise, but absolutely strengthened the ability of my fingers to find the right keys in a hurry without looking at the keyboard.