You know, I never thought about it before I read Scorch's post on this thread, but if Remington manufactured A-5's for Fabrique Nationale in the US for 12 or 13 years, do you believe they completely retooled a factory so they could manufacture two different guns based on exactly the same patent? -And that they did this during wartime, when labor and materials were in short supply? Anybody that believes they did, give me a dollar. They may have had to "tool up" to make a magazine cutoff, and they may have had to retool to manufacture a double claw extractor mechanism, but I seriously doubt if they tooled-up or retooled to make anything else.
My guess is that they started out with a supply of FN A-5 parts, not all of which were identical to Model 11 parts, but 13 years worth?? Not likely. I'll bet you that as soon as they ran out of FN parts they just started taking parts made in New York for Model 11 s, stamping them FN, and shipping them to St. Louis where they were assembled as Model 11 clones except for the addition of a mag cutoff and a double claw extractor; then finished them as A-5s.
This is all just pure speculation on my part of course, but I think its a reasonable speculation to make, and if that's really what they did, then I can see why Big Jim P may think of A-5's as "finiky" guns. I'll bet that sometime in, let's say the 1960's, Big Jim took his Remington-made A-5 (that was manufactured in let's say 1947) in for a minor repair, and somebody put a real Belgian A-5 part in it. Or maybe it was a pre-war A-5 that was manufactured in Belgium that he took in for repair, and somebody put a part in it that was actually manufactured to Remington Model 11 specs in the US sometime between 1940 and 1953.
My guess is that something like that could make a gun "finiky". And now that I think about it, it seems like its always an A-5 that somebody mentions they've had these problems with; rarely do you hear that about a bona fide Remington Model 11, which were mass produced in this country with about a million of them sold here. (I think there were far fewer A-5's sold in the US than Model 11's , but I could be wrong.)