Interesting. I'd always assumed that the heliroutes were closed to general traffic on boatrace day anyway. Even if they're not formally closed I can just imagine the clearance "can you accept a delay of up to five hours at Gutteridge" !
I was a bit puzzled by this bit:
2.1.9 The varying meteorological criteria for helicopter and fixed wing operations within the London CTR was also highlighted and discussed. The fact that helicopter traffic could be operating on the same route with no forward visibility requirements (clear of cloud in sight of the ground) gave cause for concern, especially with regard to the IFR requirements of the airspace.
We can't get into the london CTR without SVFR, and I thought that SVFR had a vis limit of 10km for PPLs and 3km for CPLs. However someone was trying to tell me the other day that those are fixed wing limits and heli SVFR vis is the same as VFR, ie coc/isos and vis approriate to speed. Anyone got a view ?