Really it depends on what you want to do at the end of the day as well as what works best for you. Personally it's something I practiced when I more actively playing for more of the challenge as I tend to not to prioritize my accuracy as much or simply might have struggled with it at the time, I would say It helped somewhat as improvement is concerned by brushing upon on certain habits and challenges I might have faced for specific maps.
It has it's benefit at least for me but feel to try something new and see how it goes, But I don't suggest solely relying on it playing the same maps over and over again, it helps to try new things and explore unfamiliar territories. likewise try to go for a higher acc/less misses than necessarily going for a S rank unless you are very confident you can FC.