Please? Let it die. Stab it if you have to.
Here's why: the term is a time-warp from a 1940s design study--University of Illinois Small Homes Council-Building Research, 1946-1949, if you want to be specific. Note the date; also note the term small. There was a housing shortage after the Second World War and the race was on for affordable housing.
(An old ad from Magic Chef, circa 1946)
There's a bit more to it than the glossing I'm providing here, but the gist is the work triangle was an efficient way of working between all three work/prep areas of a kitchen, which were defined by the stove, a refrigerator that wasn't a tribute to the monolith in 2001: A Space Odyssey, and the sink. One person (usually "mom") cooked, canned, ironed, and served the family meals. You could count your cookbooks on one hand and a typical dinner consisted of meat, potatoes, and one other vegetable. Vegetables weren't necessarily bought at a store; they might have been supplied from a home garden or a neighbor.
Contrast this with today. Kitchens can be two or three (or four or five) times larger. Our list of cooking tools and small appliances are easily doubled, if not quadrupled, from 1946, and I joke that getting some clients to admit how many cookbooks they truly have involves a therapy program. A kitchen where the clients are from Mumbai is completely different from the clients from Hong Kong, and many of my friends and clients can cook a few recipes from both.
All of which makes the work triangle about as useful as following a recipe from the 1856 Miss Beecher's Domestic Receipt Book (pages 83-84):
"...The fire must be made the back side of the oven...
If you sprinkle flour on the bottom, and it burns quickly, it is too hot.
If you can't hold your hand in to count to twenty, moderately, it is hot enough.
If you can count to thirty moderately, it is not hot enough for bread.
These last are not very accurate tests, as the power to bear heat is so diverse in different persons..."
Gee. Can't wait.
In the early '90s, the NKBA was onto a good thing with a multiple rectangle concept - the idea being where the microwave or separate ovens were considered a fourth or fifth element, taking into account families who didn't always eat together and the assumption that there might be multiple cooks. It never caught on - I suspect partly because of insufficient p.r. and partly due to too much flexibility in deciding what the four corners of the rectangle actually were.
Here: if you're going to use the work triangle, have another look at the Beecher cookbook -- it actually has some useful tips. I learned how to turn sour milk back to normal, or at least as soon as I can figure out where to find carbonate of magnesia...