Having worked in scientific and technological fields my whole adult life, my gut instinct tells me that one of the reasons it took so long was not due to simple revisions, but that the journal requested that they actually expand the study. I think they initially had strong evidence and the reviewers wanted to know more. That's why there are 10 additional PhD's on the study.
I also think that Sykes has some inside info. Maybe not from Melba, but possibly with some of the other scientists involved -- or possibly Sykes IS on of the PhD's added to the study.