I pretty much agree with the analogy, except that whereas polygamy met with increasing resistance from the state, the state has tolerated jw's position on blood as time has passed.
As for the quiet ditching with a "Brother Some" article, absolutely! They'll back away as far as they can, and then try to sneak out of the party without anyone noticing.
The wrench in the works (as usual), are those damn apostates, any number of whom are chomping at the bit to launch high profile law suits and media campaigns highlighting the about turn. If there is one subject regarding jw's that gets the media's interest, it's the blood issue. It's difficult to see how a few multi-billion dollar lawsuits with media coverage wouldn't bring the change home to roost in the thoughts of the rank and file.
Expatbrit