When your cylinder explodes and the fill station operator is severely injured, OSHA and DOT conducts an investigation. If you were the one discovered VIP'ing your own cylinders without proper training and credentials, good luck in court. I don't think there is a problem with people VIP'ing their own tanks if and only if they have the qualifications and tools; whoever thinks you only need a christmas light and a mallet, your are DEAD wrong and need to to go through a PSI course...