Stovies; a Traditional Scottish Dish from Left-overs

Stovies is a traditional Scottish dish, basically made from the left-overs of another meal.
There is a possibility that the word Stovies comes from the French "étouffée", to steam, and it would make for a good piece of table trivia, but no one can be certain. Personally I doubt it.
It is, however, commonly accepted that it was originally a Monday dish, re-hashing the left-overs of an extravagant Sunday roast, and that would lead to the meat content in most of the recipes.
So for the traditional Monday cooking, it is based in the old beef gravy, and all the components are either cooked I this gravy or heated up in it. Because of this, every component of the dish soaks in the gravy, heightening the taste.
To recreate the dish from scratch, in its very basic form, we have beef gravy, onions, potatoes.
That’s the basis of the dish, and many would argue that’s it… don’t add anything else. That’s the way some households made the dish. However, that’s not holding up the traditional conception of using up left-overs. In the old days of the dish’s history, any addition would be based on whatever left-overs you had, added to the mixture and heated up.
In our house, to add meat/proteins, my mum would brown some minced beef, and sliced or chopped sausage. I’ve also heard of chicken, turkey and more commonly corned beef (Popular at the time, tinned/canned).
Adding vegetables also enhances taste, and keeps the traditionalists happy; my mum added chopped carrots and turnip/rutabaga.
I put these additions on a Scottish Facebook site recently, and got all kinds of friendly, yet vehement comments. Seems everyone had their own version, and that became a family tradition. And anything different from the home favorite is sacrilege.
But whatever the mixture above, the bulk of the dish is potatoes; perhaps two to five times the quantity of the rest of the pot; anything to eke out the left-overs and feed the family. Cooked real slow as to not burn the contents at the bottom of the pan, it simmered for a good hour, gently bringing the dish to fruition.
I even remember mum sometimes putting a potato masher through it, just to make it more mushy.
In my house I always garnished the steaming plate with some kind of ketchup, or broon or fruity HP sauce.
Wonderful.
It makes a bit of a mockery of the dish’s primary intent to see it included in some Scottish fine dining restaurants, but I’ve seen cod or mackerel used as the protein, served with a fresh salad, hot oatcakes and beetroot.
 But it gets worse, there’s even a casserole version, topped with roasted cheese. “Serve with a sprinkling of chopped chives or parsley”…
OH PLEASE. Stick to the basics, and it’ll be braw.