Hi,
I think we could approach this in the same way as triggering actual method validation, that is provide an annotation in BV and let integrators deal with handling it.
Another idea might be to add two attributes such as preValidateInvariants and postInvalidateInvariants to the @MethodValidated annotation (final name pending).
All in all this feature is not a MUST for 1.1 from my perspective, we might also wait and see with what approaches BV implementors come up and spec that later on.
WDYT?
--Gunnar