I think it's a good way to train, except that Eric Broser generally recommends a four-way split, hitting everything directly once a week, whereas I, and many others, prefer hitting everything directly more often. I have seen Broser suggest adjustments to this program, but they usually went straight to the other end of the spectrum, i.e. full body, three times a week, still utilizing the three week rotation.
I prefer to lift heavy more often than once every three weeks, and I'm not much of a believer when it comes to tempo recommendations, so I'd want to tweak the whole program a bit. I've done something very close to P/RR/S, but I used a two-way split over four sessions a week so that everything was hit directly twice a week. For each body part, the first weekly session was heavy, or what Broser calls Power (around six reps a set, usually straight sets, although I sometimes used a reverse pyramid as Broser recommends), while the second session was a version of either his Rep Range (higher reps, chasing the pump) or his Shock (drop sets, supersets, etc.), alternating between the two every second session. This way, you get the variation he preaches but at a higher frequency.
In the end, it comes to resemble your classic heavy/light system.