The very reason I got this one wrong was precisely because of posts here that described the "Qurky Update", and thus I was left with the idea that the SET statement's actions operated left to right, in order of appearance in the statement.
I have used that quirky update thing a number of times, and it was so darn handy, that I came to believe something about it that turns out to not be true for a swap field values scenario. Quite interesting, and clearly, a good "teaching moment"...
Many thanks !!!
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