Our existing devolution certainly doesn't seem to have benefitted the regions: with health and education outcomes nose-diving in both Wales and Scotland.
Even the corruption scandals of the SNP were arguably caused by devolution: since it concentrated excessive political power in the hands of one couple who no-one could speak against, and there was no legislative second house or independent institutions capable of providing checks and balances. It's a complete mess.
Burnham's devolution will be just the same: huge amounts of money wasted, to give worse outcomes.
Don't get me wrong, I think our regional inbalances are harmful to everyone, and I'm all for trying to increase regional development.
But it needs to be genuine development - ie those regions becoming more productive in their own right. Not just regional spending of SE-generated money.