[aristus]

Another n=1, but it depends. Outside interruptions when I'm on a tear are horrible. I don't often distract myself with a full-featured computer. In fact I often spin off into "research" or fiddling with fonts as a way to let my background brain do its work. I do a fair amount of editing on my phone (!) when on transit or generally goofing off.

[vorticalbox]

What does the parse “on a tear” mean I’ve never heard it before

[defrost]

From "tearing paper", a continuous ripping action, giving rise to the english idiom "he went on a tear" .. as in "started partying and didn't stop" or "started coding and didn't stop".

[Fluorescence]

It's quite interesting looking in to it. The verb "tear" has had a meaning of vigorous haste/rushing since the 16th century so the "on a tear" idiom from the 19th century likely comes from the notion of haste rather than pulling apart material.

I believe "on a tear" was mostly used to communicate a sudden violent action rather than continuity e.g. "stock goes on a tear" not because of a steady continuous rise but because it undergoes a sudden violent change of state from flat-lining to vertical. You might be a "tearabout" or a "tearaway" if impetuous, reckless or hard to control.

I can imagine idioms like "tearing up the track" are pleasing in two meanings of the word e.g. that a horse might "tear down the track" in both haste but also in how torn up the track is from their hooves. Same with a speeding car in the days of dirt roads.

However, in modern use, especially about "productive" behaviours, I think it has lost some of the violence and gained more of the continuity sense supported by the pleasing visual imagery of e.g. scissors gliding through wrapping paper.

[defrost]

You're correct.

As a native English speaker I was aware of the older meaning, however as someone that often "quickly explains english" to ESL folk and|or non-Commonwealth English backgrounds I went with "tearing paper" as a starting point as it felt more likely to be familiar.

This is consistent with your last paragraph re: modern usage.

I've got a much thumbed multi volume OED edition on my shelves .. it's boggling how many words have half page or more entries with multiple meanings and historical backstory.

[Fluorescence]

Yeah, I look up etymology because I love how there are millennia of human culture condensed in a word as it migrates and evolves across classes, cultures and languages. Will it be Norse, Germanic, Latin or maybe Dravidic? Will it have been loaned from x to y to z and then back to x with new meanings?

I had hoped it might have come from reading rapidly in the days of uncut pages where you have to eagerly tear each new page to read it. But no, lol.