The Napoleonic era saw an increase in the size of armies, and military men experimenting with how to employ these masses properly. Massed artillery batteries, massed cavalry charges, and even some massed infantry columns.
Napoleon and Murat were limited by the communications, and command and control mechanisms of the day to use these newly massed formations more efficiently. Perhaps massed cavalry charges were a product of these limitations, and not a choice of any individual.
As with a child, armies grew and evolved at different rates at different times. For example a child may grow tall and strong over a summer becoming the perfect size to play basketball that next winter, but is too awkward to play because his/her coordination hasn't developed to accomodate his/her new size once basketball season arrives.
Armies grew rapidly in numbers during the period of the FrRev/NapWars, but had yet to have their coordination adapt to enable them to properly use their new size most effectively.
Perhaps the true pinnacle of the Horse and Musket era was under Frederick. The armies' sizes of his time had not exceded the 3C technology of the day allowing leaders to employ more sophisticated evolutions in employing their troops in battle.