Friends, this intrigues me..
Stephanie Jaworski (joyofbaking.com) has a radical tip, using frozen grated butter.
She insists it noticeably enhances texture. Unsure where this tip originates. Her bio says "Born in Nova Scotia to a British father I was brought up eating both Canadian and British food."
This is contrary to how I was taught to always mix sugar and butter thoroughly until fluffy, before adding flour.
I guess I will have to try and see what happens. Wish me luck.
Her recipe/method: https://www.youtube.com/watch?v=Tejo7q5Z9Vw
Edit 1 - Hmm.. I guess the frozen butter means it's water content is ice crystals, so not mixing with the flour. So the flour will be dry-toasted a bit more in the beginning.
Aha! Google gave me this: "Baking expert Dorie Greenspan uses roasted flour (toasted in an oven) for her shortbreads." from https://www.bonappetit.com/test-kitchen/inside-our-kitchen/article/how-and-why-to-toast-flour
Very interesting ideas. So one might take this even a step further..
Edit 2 - I believe I will try pre-toasting the flour instead.
Edit 3 - pre-toasting the flour was disastrous. Tasted like sand in the worst thinkable way.