Basically up to gold maybe plat too even if you do an absolutely atrocious engagement you generally are still in the game/may even be able to win purely on your ability to macro during engagements.
Macro is fundamentally important however I think one of the biggest issues with lower leagues is not the concept of macro, rather the ability to build while engaging in another task be that a drop or a head on engagement.
That and upgrades (although less important than macro).
E.G I am in high silver atm and vs'ed a high plat toss a few days ago. Got absolutely smashed with a storm timing but managed to hold based on my macro whilst engaging. I scouted his 4th behind the push so I should have been basically dead. However I just continued to macro and expand and even though he was on 4 base to my 3 for a lot of time and I was behind I just eventually overwhelmed him with my 3/3 vs his 1/1.
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