Sheldon was referring to a much earlier and different brand of French stem. AFAIK these later CTA products are fine and "safe" as any other aluminum alloy from that '80s period...if you really hammer anybody's brand you can make them break...I would not worry about these (unless you see cracks forming)...do the bars have that "spaceship" engraving?
IIRC. my 84 Peugeot PSV came with an aero CTA stem too. I thought that the stem actually had a pretty nice look to it but I still replaced it because it did not have enough extension as I have long arms. Opted for a no-nonsense Cinelli 1A stem with the conventional clamp design which has worked out with no problems since I got it in the mid 80's. Otherwise I don't think there was ever a problem with the aero CTA stems, at least I never heard of any.