There are numerous examples of unfair rating numbers in any rating, that's why it is called a rating game.
The T for example would have a much higher rated or faster number if the Olympic sailors raced them in events on a regular basis -
They are lighter -have more beam ,-better refined sails developed for the Olypics etc etc ,-yet are rated how comparatively to heavier boats with less beam and similar S A ?

ANY rating system contains generalities and is seriously flawed in numerous regards and should not be used beyond the local club racing level.
PLEASE REREAD the ISAF rating statement which STATES THIS CLEARLY and reinforces this commonly accepted fact.

In larger context the real point is that the flaws of this P rating system BASED ON SKIPPERS ABILITY IN A BRAND NAME CLASS does not promote the skill of sailors or the development of better design ,and instead reinforces brand classes or drives sailors to ONLY race a particular brand name or attend brand name only events ,- this ratings game flaw leads to the decline that we see in the sport as this rating system is used or applied to larger events .

We do have emerging models in each length category in general formula classifications which can similarly be used ,just as the big boat example you provided as base models in rating .
The one correct aspect of P rating is its direct equation of time to distance traveled , this real comparative numeric scale and basis should be used for all rating systems ,-Texel and ISAF should be changed to this scale for comparative -real time to distance referencing and annalysis .
The adaptation of ISAF -Texel type base rating numbers on the direct time to distance scale in P rating along with one wind speed is a superior means of rating that would corespond and promote the development and skill level and sport as we see occuring on the ISAF and Texel models ,-leading to the development of general length beam weight sail area categories for all to race within ,with much more individual freedom to modify and improve boats, not being stuck with a brand name class mfg rules and limitations to brand only modifications and add on parts gear sails and hardward . This seems a much better more systematic comprehensive approach to promote the sport, along with promoting skill levels and numbers of sailors interested .

O D is the ideal form of racing and is what historically makes the sport popular ,-the next best is formula categories that include a much broader range of builders in similar or specific OD classes together.
Complementing that is a rating system that recognizes the flaws inherant in rating schemes and the reality that the vast majority of people prefer racing in a class , that in turn helps the sport grow .

The cause and effect long term of such rating games are detrimental to the true intent of sport.-
Most instictively comprehend this and gravitate to class racing in some form or way,-be it on the course with other similar L B W SA boats,-or when ever available and just ignore the rating game .
all the best -
Carl