>>21
I can't really memorise the stages and patterns that well, so I just use reflexes, learn to see where I am, and where I need to be on the screen. I suppose if you want to 1cc everything on insane mode then you need to memorise everything, which as you say is a waste of time.
It's a good game for a break since it's not too involving - compared to RTS or RPG where I will be thinking of strategy and other things for a long time after playing.