No, it doesn't have any evidence supporting it. At least not any that you've shown us. As I, and Ancient, have repeatedly tried to point out, there are far too many variables, availability of grain being one, between HG and agricultural societies for anyone to point to a specific cause. Your evidence is a non-entity, it doesn't enter into this discussion at all.
It IS a valid theory. One that won't be proven until you take a HG society and replace some of their member's diets with grains. Until then, it's a nice supposition and it doesn't bear discussion here. Especially when you look at how the infant mortality rate of HG societies can skew the data of post 45 age expectancy. It's definitely not a foil to the Havard study, as you've been trying to play it against Convo.
So until you give us some valid scientific proof, yes, I'll bash your paleo diet.