Hi Mitch,

CC will blurr and run Sharpie and most other permanet markers.
You need to use a water based marker and this doesnt get dissolved by the CC, but does by any sweat you may get on it. I did have a pic of all the common markers and the effects of them under CC which i seem to have lost ( might be in another post) - only one that didnt run was an ARTLINE water based marker. Luckily it writes on a smooth surface OK too!