I tend to think it does, largely because I'm lazy. I don't know about the pool sand but I usd a combination of flourite and tahitian moon sand and it really makes a differeence from when I had my previous setup which was just TMS. I put a layer of flourite on the bottom then covered it with a layer of TMS. This did a lot to keep the sediment from the flourite down. my tank was clear within 30 min. I'm not sure that last bit is relevent to your post.
back on topic, the layered effect was sorta neat but It all gets mixed in as you put in new plants and rearrange them.
edit: just reread the post, didn't realize you were refering to flourite black sand, sounds cool but, no , I've never used it.