I used this for a while but noticed it greatly slowed down my Facebook in general. Ended up uninstalling it after a few days. Wish they had a lighter weight one.
Nowadays, I love going to Facebook. My news feed is completely empty.
I've probably only unfollowed about 10% of my total friends list, but the difference is immense, a lot of the noise tends to come from a small subset of the people, in my experience.
While I don't log in to Facebook more than once every six months, your observation gives me hope that I might be able to find some utility in it.