p&p CMAB encryption feature

I still don't find time to put down my ramblings on CMAB, but today i was asked to tweak the block to use client's encryption helper component instead of out-of-box encryption. Unlike other blocks, I have a great respect to this block for its sound design (as usual no COM+ support).

I wonder why didn't MSFT create a encryptionHelper component, that can be used across other blocks or a stand alone encryption application block, instead of implementing the algorithm in the CMAB block itself???