We tried this three years ago and it work pretty well. We are going to give it another go this year 2015 as well. The idea is that we will have seven tables in the convention in close proximity. One of these will be the "command table" for both sides where the armies they have will be laid out. There will be no battle on this table, it simply represents the file area, or holding area for the troops. The other six will be "half tables of 6 x 6" configuration." Each of these non command tables will have a distinctive terrain schema. One will be open plains, large down, back country, river crossing blah blah blah.
Overall commanders will receive event cards six at a time, which will give them opportunities, which, if they complete will give them victory points toward the winning of the campaign. Some of these will take place on certain "bounds" of the game, that is, the dealing of the cards. Commanders can then decide how many troops they wish to "send" to this table or that, under various player commanders. They can ONLY send troops to a table if they have a player commanders. They can send as many or as few of their troops as they desire.
The commanders will battle it out at the tabletops sent to.
At the same time the Supreme commander gets his cards, the player commanders get one or two cards of their own, giving them PERSONAL OBJECTIVES which take place on this or that table top.
Player Commanders do not have to obey orders and if they have a Personal card they want to get from another table top, they can do this. However their score will be affected by the overall score of the side blah blah blah.
Players can move from the headquarters table to the individual battle tables, but they can also move from the battle table to another table if ordered to, or they wish to "march to the sound of the guns." To do this they must draw a "transit card" from the march deck which will tell them if anything special happened on the march. They get lost, find another enemy body, make it, wind up on the wrong table etc.
Last time we played this everyone thought it was a lot of fun and one person said "This must be a great game which models real war. I was never so confused in my life, and the Supreme commander countermanded his orders to me three times.
We're hoping to do even better this year.