gustav adolphus' troops during the 30 years war where trained and expected to full fill any role on the battle field. from riding a horse and maning artillary to fighting in the pike blocks you had to be able to do it. and also his infantry could fire 3x faster than any of there rivals (apparently)

i was just surprised when i read about this. napoleon considered them so good he used there example as a basis for many of his own troops