The GPS comp is yes extremely strong, but by far, rubbish. The gap between the GPS and CAS associations has closed dramatically in recent years, and in ages gone by the CAS was equal to or stronger, depends on the year. Very aware that some/most GPS supporters would prefer to live within their own very small 6 team comp and have a home and way closed world ,where some definitely think they rule the world.
I also remember vividly when the idea of mixing games with some CAS schools would result in a ha ha ha duck egg(0) Donut etc wins for the CAS schools, is that what happened, and has it happened since? Anything but.
I also believe playing more schools, who are competitive, let's you know how good a team really is, whilst still having your own comp (which is what has happened for about 50 years before the home and away idea of about 10 years). Teams also get to experience other styles of rugby and boys you may well play with in the years beyond school.
As a rugby fan, I am sure the Joeys v Scots finale at HH will be a beauty, and the crowd will be a beauty, and a finish like that, with great weather, couldn't be any better scripted!
My Tip : Joeys by 15.