Stack leniency must not be set to a point where stacking no longer occurs. The option only exists for advanced patterns where a higher stacking leniency looks horrible or doesn't work.when stacking should occur? 1/4 streams are usually stacked with 0.1. You do need a better explanation... an Easier map with only only 1/1 and 2 (timeline distant) notes on the same point shouldn't obviously stack, so... stacking don't occurs to that point.... And so it's a bit vague.
I'd say like this it's more seeable:
Approach circles must not overlay eachother. The Automatic stacking (Stack Leniency) and Manually stacking exist to prevent this easily.As the only reason about stacking notes is this... probably...