Maybe Digby would profit from some sort of reformulation of his original question, eh?
Perhaps along the lines of: "Could it be fairly said that massed cavalry charges were one of the most decisive features of the way N's armies operated on the battlefields during the period 1792[?!!]-1815? To the extent that they were, to what degree did - and when and which - of his enemies adopt similar tactics? Lastly, was it N or Murat, or were there others responsible for developing this crushing system?"
A reformulation might clarify some of the inevitable assumptions lurking in any simple question, as well as progressively identify the answers to implicit component questions...maybe?
Curious - Howie