Ask a nitpicking question, get a nitpicking answer.
Or perhaps, like the OP, you don't know the difference between mincemeat and minced meat.
What I know is that any English dictionary on the planet (like this one or this one) will give two definitions for mincemeat (1) a pie filling made of fruit, meat, and suet; 2) finely chopped meat) and that, ergo, the distinction you hoped to make is entirely fallacious.
In uk recipe books mincemeat generally refers to fruit, suet etc., whereas minced meat would be called just mince and the addition of meat wouldn't be mentioned.

So there doesn't seem to be a clear difference between the American and British usages of "from scratch"? ~trying hard to return to original nit~

So there doesn't seem to be a clear difference between the American and British usages of "from scratch"?
I don't think there is any semantic difference between these usages. What it appears is that there might occasionally be cultural differences over how far back in a particular process train one might have to go to be felt to be using the term honestly. But even then, there is room for variation in both countries, as the term is inherently vague.
I never thought of it before, but it turns out "cooking from scratch" originated as a sporting term.
Cooking from scratch gives the OED explanation. The earliest citation of cooking from scratch that the blogger found was 1946.
I found a 1939 mention in the Ladies Home Journal.
>Make your gingerbread from one of the fine "mixes"; or you can't go wrong, you're sure to do right, if you carry on with this well-thought-of recipe, from "scratch," you know.
1938 in Automobile and Trailer Travel Magazine
>Today in trailers you may not want to start from scratch with your baked beans,
There were a few other hits before 1945. All were American.

Well that makes a lot of sense.
While we're on (or off) the topic of cross-Atlantic differences - if I tell you I've sent you a couple of brochures that'll reach you in a couple of days, how many brochures would you expect to get and how soon?
It's more Speaking in Tongues, but...
>While we're on (or off) the topic of cross-Atlantic differences - if I tell you I've sent you a couple of brochures that'll reach you in a couple of days, how many brochures would you expect to get and how soon?
I'd expect 2 brochures to arrive within 2-4 days. I know that mail service is not exactly precise. However, if you send 3 or 4 brochures, I won't think you are imprecise. If you send one brochure, I'll feel cheated.
Would you ever say "I'll send you a couple, three brochures?" (Meaning "a few") It's not uncommon here.
There's also a non-food usage of "from scratch." It's when someone's life, or someone's major project, has been thoroughly disrupted: fire, earthquake, war, bankruptcy or similar causing a person to lose everything; the lab housing the experiment you've worked on for years getting hit by lightning; etc.
The victim of circumstance must start all over again from scratch.