While the definition is true, since you want to pick nits, that assumption isn't necessarily true. It could be the acceleration vector caused by the magnus force that is a bit off. Or it could be the position equation, with the velocity vector being correct, but the initial starting position (release point) being incorrect.
All that said, it's probably easiest to just accept the lexicon being used, where velocity refers to the magnitude of the velocity vector (ie speed), and command refers to the direction.
However you want to approach this is fine with me, just let me know.