it doesnt f*$k up the macroline it f*$ks up the teeth in the elbow/fitting that grip the macroline causing it not to sit square in fitting =leaky gat.constant un-attachment and re-attachment of macroline ****s up the macroline though ,and if you dont even know what it is you are unlikely to carry piles of it about with you ,just dryfire it under a pillow ..or move out
the reason it is cold on your hand is the high pressure air zipping across it.....this is bad.If you don't have any special gadgets lying around, just grab a coin or something similiar and push into the pin on the top. The pin will be depressed and the air will be released.
It'll be loud and make your hand cold, but that is effectively how the marker is fed with air - By depressing the pin. Nothin' unsafe about it really, as the regulator will limit the pressure released (around 800psi at High pressure, or 450 at Low).
-Will