Four Finger Response

I get it...the hand is there as a barrier to our conversation, and the preference is that I direct my side of the conversation to the hand because you are not interested in hearing, nor replying, to anything I have to say.  But...if you're holding up your hand...you're well within ear shot.  And if I have to keep talking to the hand, odds are pretty good you're hearing me anyway.  Won't your arm get tired?  It's an easy discussion if you'd just put your hand down, and FAR less arm-exhausting!