I think that came from the times when it took a split second from the time you pushed the PTT till the time the X-mitter spooled up to send your voice.

"And" was usually cut off by the time your radio actually started x-mitting and the other guys old tub reciver detected a strong signal enough to break squealch.

Seems like I'v seen alot of old timers doing this... and just a few young timers.

But I agree that with the new collins and king stuff in the plane "AND" is not needed anymore. Just a bad habit.