I have a couple of questions on how JMP 12 handles process capability calculations:
Back when I worked in industry, and I was asked to cite process capability indices, I ALWAYS included some sort of graphical image too that communicates so much more about process capability over just a simple statistic like a Cpk or Ppk. Cpk's and their ilk can't show you anything about location or shape of the distribution. Can't show you unusual or interesting observations. Frankly I feel that people that blindly use just process capability indices without graphical supplements, are falling victim to a dreaded disease I call "Mononumerosis". This disease can be deadly in quality and statistics...trying to distill lots of information into one single number.
Luckily, there are several data visualization options available within the JMP version 12 Process Capability platform report architecture which help avoid Mononumerosis. The Goal Plot (useful for multiple critical to function/quality characteristics), the Standardized Box Plots, and the good old fashioned histograms (still my favorite for a single characteristic) within the Individual Detail Reports are some to consider.