I think I know what you’re asking, so I’ll give an example from my infantry training with the British Army in the mid to late 1970s.
Consider an infantry section (squad, if you’re American) moving tactically across country. They come under fire. First they take cover, second they try to locate the enemy, third they return fire to try to suppress the enemy. The section commander then has to assess the strength of the enemy in order to decide whether or not the force he has at his disposal is sufficient to deal with that threat. Generally a section could take on and defeat one or two enemy riflemen. All the preceding actions are Battle Drills and properly trained soldiers would be expected to carry them out automatically.
Now consider that same section as part of a platoon advancing across country. This time the section commander assesses the enemy as being more than just a couple of riflemen, maybe with a light machine gun too. His section cannot hope to defeat that force by itself and so he lets the platoon commander know. The platoon commander goes forward to make his own assessment and decides that the force that he has at his disposal can deal with that enemy. He then forms his plan of attack, gathers his NCOs in a safe place to issue orders for the attack, and it goes forward from there.
There’s a bit more to it than just that, but it illustrates the point. Can I deal with the threat I’m facing? If yes then do A, if no then do B, and so on up the formation. You train in these Battle Drills over and over again so that it becomes second nature, and so that you are not overwhelmed by the decision making process. The fewer decisions you have to make the easier it becomes to deal with a problem I was a footslogging infantry platoon commander as so my training and experience is limited to just that type and level of operating. I have no idea of what mechanised infantry, tanks or combined arms did, or do now, but they must have had, or have, similar Battle Drills and decision making ‘trees’ too.
Less enthusiasm, please. This is Britain.