now we are getting into semantics. Always fun
Prologic II uses an advanced decoding algorithm to 'create' positional audio where previously there wasn't any. Eg, stereo music tracks. It can also further enhance a prologic soundtrack, splitting the mono rear channel into separate left and right. Now all of this is guesswork by the decoder, but it does a good job.
Working backwards from that, if you know how the decoding is done, you can create your stereo signal in such a way as to predictably position specific audio samples in any of the 5 speakers being driven.
Just like prologic 1 is only a stereo source, but at the audio mastering stage, sounds can be positioned anywhere front/left/right/rear. Its simply that the carrier is two channel analogue, rather than digital.
PLII is the same, but the stereo can carry encoded front/left/right/rearleft/rearright signals.