It's funny how a gesture in the regular world can mean one thing, while the same gesture in the piping world can be something totally different.
I went to a doctor appointment with Small Son today. The doctor bustled in after an interminable wait, greeted me, and held out his hand. This, of course, was part of the greeting, so I held out my hand and shook his. This was the appropriate response, and the meeting went on. It was a rather worrisome meeting, so it was on my mind for some time after that.
Several hours later at band practice, I was tootling away, warming up my pipes but still thinking about the doctor's appointment. Pipe Major Jason approached me and held out his hand. I held out my hand, as before.
But this wasn't a greeting.
I forgot I was now in a subculture where there is a different body language. There aren't usually any greetings at band practice. Maybe a nod of acknowledgement that, "Oh, I see you showed up to practice this week." A mental 'checking you off' on the list of members. That kind of thing. I guess we consider this new practice session as not 'new' at all, but a continuation of last week.
In the pipe band world, when a pipe major holds out his hand to you, it means your chanter is out of tune and he wants you to give it to him so he can tune it.
Jason laughed and shook my hand anyway.
Then he took my chanter and tuned it.