Judy & Sue:

My experience with the flat rate envelopes has been similar. I've always been afraid of them opening up also. I had checked a while ago with the postal manual and it states that a flat rate envelope has to close with the sealing flap and not need any additional assistance (tape) to keep it closed. However, they do not say anything about tape to add extra "insurance" for security purposes. My experience has been OK so far and do send to NYC quite often. I only use the clear tape not Priority Tape to seal the envelope. Once the tab has been sealed on the envelope I use clear tape to seal the flap. Then clear tape (the wide stuff) to seal the two edges without wrapping the tape around to the other side. Then the computer printed self adhesive label covers a good portion of the tape when it is applied. So far (fingers crossed) there has not been any problem. I have seen times when people have used the priority mail tape to seal their envelopes and the clerk has questioned it. I don't know if any of this helps but it has worked for me. Oh the wonders of individual clerk's interpretation of the rules!!

Garry