There is nothing tactical about saving a game, but it’s an important tool to get through the game, just like a weapon. The game saves at the start of each conflict, which gives you a chance to take a mulligan and do it over.
Thankfully, the game saves automatically because battles can go bad very quickly. Of course, you will never make any serious progress if you redo each battle to get it perfect.
There is a big difference between good enough and a miserable encounter. Still, the important thing to keep in mind is that the autosave begins at the start of that combat.
Replaying a losing scenario is not fun, and that is why saving is also an active part of getting through the game. When you are not engaged in combat, you can manually save your game.
It is easy to forget about this because of the autosave, but it is a good practice to manually save before or after a huge battle in case something goes terribly wrong in the next conflict.