Dude, you completely missed the point of that post. It literally says in the second sentence that Scheme's numeric tower was borrowed from Common Lisp. The point is that if Scheme's numbers were like the rest of Scheme, they would be horribly impractical.
That post complains about numerical tower not belonging to some library and being more generic. I don't understand how that is more/less practical.
Common-lisp also has a numerical tower afaik. I don't understand how does that make it "better for real work(tm)".