Ahh, very enlightening observations and insights. The point about training and practice certainly would explain Prussian capabilities during the Seven Years War, as Frederick's army practiced in large masses regularly over the years, perfectly underscoring your point that it's tough to perform in battle what hasn't been previously practised.
To a great extent, having roughly similar tools of command and control, the Coalition powers might be said to have fallen out of practice by the Revolutionary and Napoleonic period, and possibly to have failed to relearn very quickly what value there was in massed cavalry action, on top of what may have been some profound changes in the corporate sense among officers of norms and capabilities.
Very helpful - many thanks :o)
A happy holiday to you - Howie