This is an article waiting to happen, but I will sum up.
Napoleonics gaming -- pace the beloved KS -- begins with the skirmish-as-battle begun by luminaries like H.G. Wells and Don Featherstone. They lumped a bunch of fellows from the same regiment into groups of 20, roughed out the regiments that were at a particular battlefield, and fired them at each other. No basing, other than what you needed to make a fellow stand upright, ground scale was not an issue and neither was time scale. Most of the stuff was either 54mm or, later, 25mm.
As time went on -- I point this to the late 60s into the 70s -- you saw fellows start to care about ground scale, figure scale, &c. This, then, opened the issue of who the player actually is. A brigadier? A corps commander? Napoleon? For many years, rule sets struggled with the issue of balancing scope with playability. In truth, most of the classic-era games were battalion level, but most everybody (not all to be sure) wanted to play Austerlitz, Waterloo, or Leipzig. This usually broke the game in horrific ways. CLS, Empire, and any number of lovely homebrews cracked under the weight.
Enter games like the seminal "Volley and Bayonet" by Frank Chadwick which turned the base units from battalions to brigades under the twin arguments that brigades were actually the primary MEs for high-level commanders like Wellington and that you could successfully game Waterloo in a lifetime. Others have followed including the well-regarded "Grand Armee", "Blucher", "DBN". and the horrifically-titled "Snappy Nappy" which I've long thought British players would associate with a child's nether-garments.. Others took matters in a different direction trying to distill out the granular detail that made older rules such a slog at high level while still keeping the battalion as the ME.. The greatest of these was surely "Shako" (I and II) although I have a soft spot for "Le Feu Sacre".
Other systems have tried to put the granularity and detail into brigade-level games. The two best here are "Napoleon's Battles", which I still prefer in the AH edition, and the estimable "Age of Eagles" which is a now well-developed riff on "Fire and Fury".
And, of course, all along folks have clung fiercely, although in diminishing numbers based on my experience, to their "hyper realistic" games. The best examples I can think of here are "Empire", "General de Brigade", and the depressing slog that is "Carnage and Glory". To those playing the latter: PLAY THE ENTIRE DAMN GAME ON A PC. YOU'LL LIVE LONGER, HAPPIER LIVES.
With all this, one would think people would tire of writing rules, but part of the spirit of minis gaming, I have come to think, is a desire to get what you think these battles should look and play like to the table and share that with others.
"Et Sans Resultat", named after a famous quotation re: the Battle of Eylau, seems (I've not played it) to be poking at that middle space between Empire and Blucher. The ME is still the battalion, but it's represented as a single base and orders are issued at the divisional level (a choice I find interesting). The company behind it is producing a lovely line of campaign books around the key battle sequences during the history of the First Empire. They have also shown themselves quite the aggressive convention demo team.
And that's prologue.
Doug and I have discovered the joy of TTS and I am NOT going back. Next year I'm off to visit Aspern-Essling, Wagram, and, hopefully, Eckmuhl, so I must build games around them. We're already pounding away at the early part of that campaign using "Flight of the Eagle" elsewhere. A-E is the best regarded of them (really one of only three battles where the sides can be said to be even (bonus points for guessing the other two)). I am going to build an ESR A-E set in TTS and will be inviting ACD minions to play. This will be televised...Twitched anyway.
Also, it is hoped, the folks behind ESR will be joining the ACD crew at Historicon.
Doug and I are relieved of all other responsibilities and will be yelling at each other in highly-inflected German.
Selah.