Those dx10 effects was not locked, but were not supported on dx9 hardware. Were talking about only minor graphical aspects:
Soft particles, object based motion blur and something more which i can't remember. Apart from those, there was no difference in the graphics when running crysis in DX10@Vh and running dx9 with the "veryhigh tweak" by altering some cvar config files.
They are purposely locked, and we all know why