Glad to hear that you are not sledging the whole tube. From earlier posts that's what it sounded like....
Auminer-I think what he is doing is tapping the top of the neck to release the vacuum so if something does drop on the actual tube it won't exploded...breaking the seal on top won't make the tube implode it only releases the vacuum and let's air into the tube slowly. I only do this if the cone is stuck on the tube with a lot of glue or whatever is used to hold the cone on. It's actually safer to do this before taking off any cone just to be totally safe.