Despite my best efforts, I have had mixed results at best.
As Stiles Thomas taught me, I use the term mostly for bad puns (is there any other kind?). See Jerry Barrack's photo above, which features a sign that says "No pishing," often misread as "no fishing."
While reading one of David Moldawer's weekly essays on writing ("The Maven Game"), I discovered another meaning.
Moldawer began his essay this way:
"Last week, I misspelled meshuggaas. It was a real meshuga thing to do. What a pisher I am."
I wondered: What does misspelling words have to do with making sputtery noises to attract birds?
It turns out that the first online definition of "pisher" is:
"An inexperienced person or someone of no or little importance." Yiddish.
Oy vey! Back to Square One. When it comes to being a pisher, I guess I am one.