Matthew F.,
That is correct. Both the "jump spin" and "jab step" are considered moves "from the rubber". If the move is made to 1B, there must be a throw and it must be to 1B (as opposed to an F3 who is not close enough to 1B to even attempt a play). If the pickoff throw goes out of play, any runners are awarded one base.
The only "exception" (really more of a "different case" than an "exception" in my mind) I can think of would be if the fielder receiving the throw did not "handle" the throw and, in his attempt to retrieve it, applied "additional impetus" to the ball which caused it to go out of play, the award would be two bases instead of one.
JM
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