RM's curiosity and obsession over PJ III is easy to understand. The guy is very athletic, and seems that have the tools to play the 3/4.
Reminds me of my obsession with/defense of Patrick O'Bryant a few years back, when he was perfect size, athleticism to fill the need at the center spot. Trouble was, he just was not productive on the court, mostly because he seemed to lack a motor. It was very frustrating watching that unfold.
I suspect we will see the same thing happen with Jones. Danny will probably give him the opportunity to show he can assert himself, and if he does, he will keep him. If he does not, he will cut him.