EASA CS-MMEL for CVR Items

I am a member of the US Master MEL Industry Group (MMEL IG). We are a US airline industry group which collaboratively will work with the FAA on Master MEL policy.

I'm also on a subgroup of the IG who have been tasked to look at the FAA policy relating to CVRs. Our rules read like EASA rules (e.g., in OPS 1.700/.705/.710), a commercial aircraft must be equipped with a working CVR; one of our operational rules require a CVR to be "continuously operated" from before the before start checklist to after the final shutdown checklist. 

My question is how does one go from OPS 1.700, 1.705 and 1.710 to the EASA CS-MMEL where an EASA Operator, under item 23-71-1B, can operate for up to 8 segments or 72 hours with an inop CVR (but in this case the FDR (if equipped) must be operative. Was there a deliberative process that came up with the 8 segment/72 hour standard?  

As a US 121 Flight Operations Officer, I am not trained in all things EASA, so please pardon my ignorance. That provision reads a lot like our current MMEL PL29 (CVR) and PL87 (FDR), which the FAA wants to, for lack of a better word, repeal.