"celebrated WT scholars" puts me in mind of Samuel Johnson whom I misquote:
A WT scholar is like a dog walking around on its hind legs; it's not that it's done well that's cause for celebration, it's that it's done at all.
As for your "what if" question re: 607. Essentially the Society has already done that with its redefinition of a generation. Why change the dates 607/1914 when you can, instead, eliminate their significance altogether? What does it matter when the kingdom was set up if the "generation" can last forever? Incredibly the Society has stripped 1914 of all meaning by (i) declaring that the kingdom was set up then but invisibly (here Carl Sagan had it right!) and (ii) that this date marked the start of a time period which would see the end of the world, but which period could go on indefintely. However, this second sleight of hand by the Society overestimates the thinking capacity of the dubs who still remain.
It's hugely entertaining to watch dubs such as scholar mentalmasturbaticus trying to defend dates that mean nothing at all for current WT eschatology.