P-mount vs. 1/2" cartridge

Ah, the amazing cartridge and stylus.  A technical dinosaur, yet simultaneously our hero of the day.  At face value, the thought of a needle grinding into grooves on a piece of vinyl, giving us our performance seems cruel.  One could also argue that the bond these two share means no performance will be exactly the same, ever again, lending some romance to the experience.  Engineers such as myself pondering this feel somewhat obliged to pay attention to the show and give it due respect.  Perhaps this is yet another reason I gush over records as I talk to friends and strangers alike.

This brings me to the piece of mental floss at hand.  My Denon DP-7F (circa 1985) has a P-mount tonearm.  This means changing the cartridge takes only a minute, and is set in place with a template of female receptacles in the arm itself for the mating cartridge leads.  The cartridge itself is secured with a single flathead bolt (and nut on the opposite side) which goes through the body.  There are typically no adjustments or calibrations to be made, as anti-skating and tracking force were hard-set in at the factory.  Changing said cartridge is quick, painless, and very convenient.  All that being said, models in this P-mount style have dwindled as it is not the style of choice for quality turntables...

For that we turn to the venerable 1/2" mount (below), whose standard and bar have been set for decades, and still follow true to the present day (never mind the style of the cartridge itself can be all over the map).  Ortofon, Shure, Audio Technica, Rega, and dozens of other brands all compete for your hard-earned dollars in this market.  The price range also covers as wild a spectrum as you can imagine.  It's fair to say that at some point a diminishing return enters the equation, but this isn't the point of the post.  These cartridges attach to the tonearm with a pair of flathead screws which again go through the body and are secured with washers and nuts.  More care, time, and effort is required in this installation, as you can change the angle with which it sits, the position front to back, and you are responsible for removing and reconnecting the four leads (two leads for each channel).

I've heard a P-mount Audio Technica very similar to mine show great definition on a nice setup.  How much difference do you all suppose there is in the potential of the P-mount architecture vs. its 1/2" brother, assuming for the 1/2" you aren't buying a beryllium-carbide, 40 kilo-newton rated model with a side of unobtanium included for fininepeptide replenishing?  Does the design somehow inhibit the stylus from singing with the best of them, or did the P-mount just never go the same distance because it was assumed the turntables they were on weren't worth the effort?  I realize this doesn't change what's available these days, but curious minds want to know...

For extra credit, but no definitive answer on the big question:
http://eu.audio-technica.com/en/resources/tutorials/A%20Guide%20to%20Phono%20Cartridges.pdf