I am in favour of cyclical capital buffers but not the kind the BCBS has developed.
I have attached a link to a post by Charles Goodhart and Dirk Schoenmaker which highlights the problems with the BCBS Counter Cyclical Capital Buffer (CCyB) and proposes an alternative more rules based approach.
While banking is procyclical, the capital framework is largely static. The countercyclical capital buffer is discretionary, with potential danger of inaction, and is also limited in scale. This column proposes an expanded capital conservation buffer, which would act as an automatic stabiliser. This could incorporated in the next Basel review and the upcoming Solvency II review.
I have my own preferred alternative approach to the cyclical buffer problem but I agree very much with their critique of the CCyB.
Their post on this question is not long but worth reading.