I met with Richard Mount (SLAC Computing Center Director; on G4 steering board) yesterday morning for about an hour.
He admits that the testing of G4 is weak. There has been a big political effort to bring in non-G4-member experiments, and it is now set up so that there are no 'special experiment members' as there has been so far. A Technical Forum will be set up, chaired by the CMS physics coordinator (I think that's who it is) which will deal with long term issues (such as validation; not bug-fixes). This is the mechanism he sees for addressing the physics content oversight of G4. We will be welcome to attend the Technical Forum meetings.
In the meantime, he was favourable to the idea of Tatsumi Koi at SLAC working with us to set up the EM physics test suite. He needs to talk it over with Makoto Asai and Tatsumi first, of course. Makoto is to be our local contact for future G4 issues that come up.
He also suggested inviting the G4 EM guys (Laszlo Urban and Michel Maire) to visit us this summer. I suggested that the DC1 workshop in mid-July would be a good time. Then we could over in detail all the EM/MS physics and validations with them.
He also suggested we resume regular meetings with SCS (not just for this issue), probably monthly or bi-.
On the DC1 CPU time issue, he reassured me that we should easily get the ~1% of the compute farm that we need to do this.
So, he didn't have all the answer to make the G4 team well again, but he is certainly deeply concerned about it, and is genuinely interested in GLAST's successful use of it. Hopefully that will gel into real action!