One sub point that Argo didn’t mention is that if you commit the transports to the attack, and the naval battle fails, that the whole surviving group retreats together, with the land units stuck on the transports until the next turn. This makes them very vulnerable to being destroyed, which makes this type of combined sea/amphibious attack high stakes.
This is also why you have to commit to the battles at the same time; not only does it keep the flow of play clean but it also forces you to analyze all the risks you are taking at the same time. Reshuffling your unit allocations in other planned battles after the first combats are seen is also a no-no, though in a friendly game it is ok to make some revisions.
Still, since you can choose the order you fight battles in, this can be helpful. You can see the outcome of 1-2 big battles, and then know whether the smaller battles are worth fighting to the bitter end, whether its more important to take the territory vs just clear it. You do have to fight at least 1 round of combat for every declared battle, my point is that gaining certain information as to the outcome of one important battle can be instructive of the need to fight other battles to their bitter conclusion or withdraw early.
We fight in this order, not sure if its required in all versions by the letter of the rules, but it can make the game have a cleaner flow…
Declare all combats, unit buy is sealed and cannot be changed after we begin to do;
strategic bombings in any order then
sea combats without land element in any order
sea combats with a landing in any order
land combats in any order
don’t do any noncoms zero zilch none until now because it keeps the separation of turns and moved units cleaner I realize its tempting…
lots of teams only have 1-2 combats to declare per turn so focusing on doing all your combats first (and ignoring units that will noncom) is also an easy way to keep your mind focused on one task at a time; things that fight get committed first and everything else can be contemplated at length after combats are resolved.