It is indeed as she states: The immature fish (the fry) have
scales, then shed them as they mature. The Torah requires that the *adult*
fish have scales and fins to be deemed kosher.
The confusion stems from the Talmud's statement (in Maseches Chulin)
that a fish that sheds its scales when fighting the fisherman is still
kosher. This is derived from the verse in Leviticus, "Any [species] that has
fins and scales in the water, those shall you eat." The implication here is
that in the water it had scales, but not out of the water. To what case
does the Torah allude? In our case of the fish losing its scales in its
struggle to free itself of the hook. It is still a kosher species.
The other case, that of the fry that sheds its scales upon maturity,
does not qualify under this rule, because for a part of its life "in the
water" it had no scales. As a species that exhibit this behavior, swordfish
therefore do not qualify as kosher.
For a discussion of the controversy raised by the Conservative
Rabbinate, and the Orthodox response, see the entry under "Swordfish" in
Joseph Telushkin's work, "Jewish Literacy."