A Quick Practical Joke, re: Mad Dogg's Age

My wife found a coupon for hearing aid batteries. A plan was quickly hatched.

Readers with long-term memories will recall how my co-worker Mad Dogg turned 30 recently, and wasn't too happy about suddenly being "old". The plan was simple. I came into work before he did, and I taped the coupon to his monitor.

I went back to my office to wait. Quite a lot of time passed. Finally, I got a phone call from Den Mother, who works in the same office as Mad Dogg. Her desk is right next to his. There was laughter from multiple people in the background during this call.

"Hey Jeff, could you please call Mad Dogg and explain the coupon to him?"

I was prepared for, "Could you call him and fess up?". I wasn't quite prepared for this. Den Mother had asked Mad Dogg, "Do you want me to tell you who did this?", and he responded with, "No, because whoever did it is going to fall over laughing at the fact that I don't get the joke."

So after all this was explained to me, I called Mad Dogg. The conversation went something like this:

Me: "I hear you're a [i should have been nicer in my choice of nouns]."
Mad Dogg: "Is this because I'm getting old?"
Me: "Of course!"
Mad Dogg: "See, I just didn't know what it was supposed to mean."
Me: "Hey, I see a coupon for hearing aid batteries, and you're the first old person I think of."
Mad Dogg: [long pause], followed by [explicative]

Apparently, when you get "old", the mind is the first to go. You young pups out there, take note.