Yes, I saw it - in fact I helped Trevor and John with the script, for which I received a generous credit in the prgramme.... but I can't say I greatly cared for it. The "boy" playing Peter had his testicles around his knees, therby making a mockery of the whole concept, and if the actor/actoress playing Peter's no good it doesn't really matter what else works (e.g. the recent movie).
T and J fell in love with Barrie's stage directions, and had a Barriesque narrator reading them from the wings, which in my view undercut Barrie's drama - i.e. everything was repeared: once by the narrator, and again in the action. But it received mostly good reviews at the time, I think largely because everyone was so happy to see PP more or less as JMB wrote it, rather than the drab pantomime that had been trotted out annually up until then.
The basic problem with giving PP to GOSH in 1929 was that it became a money-making machine for the hospital. Prior to 1929, no expense had been spared in its annual revival, but from then onwards economy was the order of the season, with a general dumbing down in order to gain the maximum number of bums on seats. In this respect the RSC production shone, but in my view (and - I gather - the Queen's!) it fell far short of perfection.