I’m not sure I would’ve called it a “miracle” – but I use graphite on my rails to improve conductivity.
I wrote a piece about this for the May, 2015 issue of Model Railroad Hobbyist. And boy, did it ever generate a lot of comments – both pro and con. (You can search on the MRH forum if you want to go down that rabbit hole.)
I also shot the short video embedded in this post, to demonstrate how I applied it to my Port Rowan layout.
I still use graphite. It still works beautifully for me.