Copperslip uses a grease carrier - it lubricates.
The argument against using it on structural fastenings without a secondary locking mechanism (ie tab washer, split pin etc) is that it *could* cause them to loosen when subjected to repeated vibration but equally importantly it can lead to the fastening being over tensioned and weakened (as a higher torque is needed to overcome the lubricating properties).
But if it works for you, knock herself out. I'm not telling anyone what to do - I just asked why people insist on lathering it all over wheel studs (and shock mounts).
Strictly speaking, ferrous to ferrous fastenings which are either non-structural or have a secondary locking device. But of course it's used all over the place with no problems by millions of people. It's great for stopping wheel and swinging arm spindles from sticking on bikes with 'normal' suspension
I tend to use acf50 grease or chromate paste on most stainless / alloy fastenings on my bike but I use blue loctite on shock bolts and nothing on wheel studs.
But that's just me - its your bike(s), do what you like