Jim,
That explains something I had noticed at stations on the Cotswold Line this morning, as I was puzzled to see that the new HST▸ stop markers Worcester-bound are too far off the end of the platform for the TGS to be platformed, but I now see they only come into play with a reverse formation.
Will just have to wait to see what happens at Moreton-in-Marsh in reverse though, as the starting signal protecting the single line to Evesham and the token machine used by drivers are at the end of the platform, so it may still be stop with first class and two standards on and shunt forward if someone needs to get a bike from the TGS, or ensure any bikes are in the front power car on leaving Oxford.
Ah, forgot to mention that the "reverse formation" rules only apply if operations allow (i.e signals)