The impact of even 0.5% of a pay rise being non-pensionable will turn a 2/3 scheme in to more like a 1/2 final pensionable salary over the course of 38 and a bit years.
If you don't believe those figures then work it out for yourself and see how much money you'll be losing.
Of course, the 'yes' supporters will say the cap is only in for 15 years but is anybody really naive enough to believe it will ever go?
If the pension proposals had been to change from a 2/3 scheme down to a 1/2 pay or less you can be sure the reaction would have been completely different.