Managing fatigue becomes quite important in very large battles with multiple stacks. Although troops will never regain enough energy to get to the 'fresh/quite fresh' stage, even 'tired' will do for troops with moderate honor (like 2 or 3) and well led.
The trick in defensive battles is to make the best match of what you have against what the enemy currently has on the battlefield. In the meantime, rest the troops you won't be needing for the current stage of the battle.
There is a tendency to overwork cavalry in long battles, and I certainly did (and still do, to some extent) when I was learning to fight these types of battles. It's verrrry inticing to chase every router off the field with your cavalry but after the 2nd or 3rd wave should be avoided because fatigue will slow them considerably and they might easily be caught by fresh enemy cav entering the field.....and trust me....I learned this one the hard way
Another thing to manage is formation for depleted units. As an example, your yari spear unit has been reduced from say 60 to 30. If the unit started the battle in four rows, they may be in only three or even two rows now. Not good for resisting a cavalry charge. Reconfigure them back to four rows. Yes it shortens the line which might allow a 'wrap-around effect' but I've found deeper ranks resist charges better than shallow ones. This is most certainly true for ashi units who prefer the 'comfort' of mass.
Be picky about which units you choose to withdraw from the battle. Even archers with depleted ammo can be of use if they can attack downhill or hide in forests. I rearrange mine into 5 rows (from the 3-deep formation they use when shooting) and put them somewhere to rest until needed. On more than one occasion they have helped plug a hole in the line that might have spelled defeat had they not been there.
A bit of a ramble, I know, but just topics I thought went hand-in-hand with managing fatigue![]()
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