I am unfamilliar with PDT. unless you mean PDR?
I'm assuming it was a typo.
The Personal Defense Readiness Program is unlike any other 'Reality Based' training system which is sort of a buzz word in martial arts / combatives circles.
It is the only behavioraly based system meaning it incorporates a response to what 'real' bad guy behavior is. To compare most systems are attack specific meaning bad guy does a and you do b contradicts what are brain wants to do in survival situations and puts us way behind the curve in regards to action vs. reaction.
All the drills are modeled around bad guy behavior and so many people will witness that when confronted with violence they report it was just like 'doing the drill'.
COmplex motor skill vs. complex motor skill leaves for zero margin of error you can reference this in the Blauer CF videos.
Watch a style or systems video and watch only the bad guy; is he /she reacting like a real bad guy? What you will tend to see is the bad guy thorugh a MA type attack and then freeze while the good guy aplies his technique, aggression stops as does resistance etc... Plainly it looks fake.
Watch a SPEAR system video and watch the 2 role players. It looks like a street brawl but once you can indentify the principles and tactics used you will see the system applied.
There is so much more that makes it different. My first advice is too watch all the Blauer CF videos in no special order and you will have a better grasp of things. Next you can go to www.tonybluaer.com
they have a world wide coaches map and I know of at least two in the VOorhees, NJ area. Carlo and Aka and they are great guys.