Obviously FO was worried about handing the keys to JBJ, otherwise they wouldn't have brought in Grady. At this point i believe Grady has done enough to win the job and JBJ hasn't. couple that with JBJ still having options. He is young enough that this seeming "demotion" should not adversely effect him for too long. it will test his character and the hope is give him hunger and chip on his shoulder. that combination can be extremely beneficial.
I think they will send him to pawtucket but tell him to keep his bags packed for the inevitable DL replacement for GS or victorino.
We may have caught the proverbial lightning in a bottle with GS and should ride that low cost/high reward horse until it keels over. Meanwhile JBJ can get nightly work in AAA.