[CQ-Contest] Zero Beat ? Not everybody does !

[jpescatore at aol.com]

160M and/or 10m contests with poor conditions are good examples of why you need to add item 5 to  your list:
5. Often two running stations are sharing the same 500 hz window. They can't hear each other (or are just fighting for the freq) but others can hear both.  
Often a source of NILs for the running station, for the S&Per with wide enough filters, this can lead to a twofer QSO when both respond to you and both ack.
73 John K3TN