While playing Touhou: the Embodiment of Scarlet Devil, I noticed in the summary statistics of a play that the game keeps track of your overall Slow percentage. I've found that using Slow definitely helps me with fine tuning my movement when fighting bosses, so I'm trying to force myself to use it more often to help me get through tough battles (my tendency to forget to use my bombs is another matter entirely).
However, is this detrimental to how the game calculates my score? Is using Slow a bad habit to form?