Hi again, RR.
First of all,
PT has nothing to do with scales, modes or pentatonic boxes. Nothing whatsoever.
If you want to be able to see your whole fretboard as a unit, then you should order it; if you want to be able to create melody and harmony lines without wondering 'what scale?', order it. If you want to have music simplified down to its lowest common denominator, order it; if you want to teach your teacher a lesson he'll benefit from, order it. If your ability to improvise is not what you'd like it to be using all those scales and modes, order it.
Have you read
these testimonials? Are you aware there's a private PlaneTalkers' Forum where we get right into it all on a daily basis?