I heard something similar from a reliable source at the end of last year, although it was in reference to Sandhurst only. If it was not for this (secondary source!) corroboration I would take this wish a large pinch of salt due to the points raised regarding access to seaborne training, lack of a runway and lack of the extensive miliary training areas that surround Sandhurst.
My early memories of Cranwell were coloured (light blue?) by the aircraft activity on the other side of the road and this helps reinforce the characteristic ethos of each service. Compare this with the Royal Air force patches mentioned in another thread!
We have this supposed motto in our service called "RISE" for respect, integrity, ethos and service. The ethos element is being eroded by those military, political and civil servants above us who see such sacrifices as expedient to their careers. I therefore find myself losing respect at a rapid rate. How about "Aquiescence, Ridicule, Self-interest, Expedience" as a motto, with a suitable acronym!