Evacuation Day

1) Boston, March 10, 1776. The four British generals in Boston (Gage, Clinton, Howe, and Burgoyne) debate their exit strategy after the Colonial forces have occupied Dorchester Heights)

Gage: Gentlemen, it appears that we can complete our withdrawal a week from today.
Clinton: Rot! We can withdraw in five days. I suggest the 15th.
Burgoyne: (languidly) Oh how classical of you, my dear Clinton.
Clinton: Beg pardon?
Burgoyne: The Ides of March, old man. Beware the Ides of March? Shakespeare and all.
Howe: Trust you to think of a literary allusion, Burgoyne.
Gage (irritated with the lot) Then what's your suggestion, Howe?
Howe: We shall certainly be ready by the 20th...
Clinton: Day late and a shilling short again, Billy?
Howe: That would be the vernal equinox, if we're after allusions. And in that case, it can't be the 17th.
All: Why not?
Howe: That's St. Patrick's Day.
Gage: St. Who?
Howe: St. Patrick; patron saint of Ireland.
Clinton: If he's their patron, he'd bloody well better get on it.
Howe: It's a holiday for them.
Burgoyne: What reason have the Irish got for a holiday?
Howe: I can't imagine, but it is. But gentlemen, suppose that in a century's time it's the Irish who are running Boston...
Clinton (musing) There are already some here, y'know.
Burgoyne: And they do breed like rabbits.
Howe: And one of their politicians cooks up an idea to make St. Patrick's Day a holiday under cover of celebrating our withdrawal...
Clinton: Outrageous!!
Gage: Hmm. Serve the bloody Yankees right though. Right then, 17th it is?
All: St. Patrick's Evacuation Day!

2) Today, I read solemn treatises (even from the BBC) assuring the Webducated that a St. Patrick's Day pinch is amongst the most revered of holiday traditions. Having grown up with a large quantity of Irish-American in-laws and out-laws, I scratched my head in confusion; never heard of this. I then asked my spouse, who bleeds green if she's cut today, and who has various relations who were connections of the late beloved James Michael Curley, and who had (to a point) a good parochial education. She thought for a moment and said, "must be from Chicago."
I believe we're witnessing the birth of an urban legend. In my environs, and I think around Boston, anyone who delivered a pinch on St. Patrick's Day was (and is) likely to get a punch in reply. Don't believe everything you read on the Web.