Phil, also check out my answer in
this thread about Drive On Loenen.
To attach all the artillery together, hold down the Shift key and left-click on each artillery unit in turn until they are all selected. Then issue an order to this group of units. You will see that one of the selected units takes charge of the rest!
Whether you split your forces depends on what you want to do. In Drive On Loenen, you have a Regiment containing three Battalions and a few other units. If you want the whole Regiment to do the same thing (for example, make a coordinated attack on Loenen), then it's usually best to issue the orders only to the Regiment HQ. It will then give orders to the other units to make sure they all move together and start the attack at the same time.
If you want two battalions of the Regiment to do one thing, and the third battalion to do something else, then issue one order to the Regiment HQ, and a different order to the third Bn HQ. For example you might order the Regiment to attack Loenen and order one battalion to attack a different objective.
In general smaller units (like battalions) react to orders and move faster than big units (like Regiments). The tradeoff is that coordinating the efforts of several smaller units is much harder than allowing a single big unit to coordinate itself. For example, giving an attack order to a Regiment HQ will take a fair while for the order to be given to each Bn and then to each Coy; and then a fair while for the units to move to their attack position (called an "FUP" or "Forming Up Point"). However, all three Bns will make the attack at the same time which is a very powerful force!
Issuing separate attack orders to each Bn HQ will take much less time for the orders to be given to the Coys; and the Bns will move quicker to their FUPs. However, unless you are really really lucky, each Bn will start the attack at a different time so the enemy only has to deal with one or two at a time, instead of all three.
Deciding when to use a big force instead of several smaller forces comes with experience, so keep trying different combinations and see what works!
You will also be glad to hear that a Strategy Guide will be coming out shortly after HTTR goes on sale that will contain these and other useful tips to help you learn to win the game!
Regards
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