CRC will make all sorts of claims about what their product is good for, but you would have to take most or all of them with a grain of salt, as the claims are all generalisations, not to mention marketing hype.
The simple fact is that any liquid applied to rail will attract dirt and this will eventually have to be cleaned off. It does not matter whether you use CRC, Baby Oil or Chanel Number 5, the effect is always
The best product for improving rail to wheel contact is graphite, as it is most definitely conductive
, non-corrosive, and most importantly dry.
It does not attract dirt and is also able to spread itself around the layout if you just apply it in one place. You can either use graphite sticks as Roachie does, or in powdered form, or simply use a graphite pencil to run along each rail.
I know of organisations that run exhibition railways that operate every day for many hours a day, and many of them use graphite to improve power collection.