Navy PTA clause

CAAFLog has this interesting post and question about a new (?) clause in standard Navy PTA’s that remove good time credit.

This Agreement constitutes my request for, and the convening authority’s approval of, deferment of all confinement suspended pursuant to the terms of this Agreement and deferment for the days of “good time” (as defined by SECNAVINST 1640.9B) that I may earn while in confinement prior to the convening authority taking action on the sentence.  The period of deferment will run from the date of sentencing until the date the convening authority acts on the sentence.

And here is CAAFlog’s question:

Obviously the effect of this provision in 99% of cases would be that the accused gets no credit for good time.  The clause raises some interesting questions, like: Has anyone seen this litigated anywhere?  Have any judges accepted it?  Will brigs honor it?  Can an agreement between the convening authority and the accused affect the operation of a Secretary of the Navy Instruction?  How do brig CO’s feel about a judge advocate removing one of the tools he or she relies on to run his or her command?  Did this address an issue that arose and needed a fix?