"I suspect they will insist on watertight contracts before committing those billions even now."
There are no water tight contracts, they found that out in Venezuela - and at some points in the campaign Salmond was sounding quite Chavez-like. I'm sure the multi-nationals won't have missed that.
As for the English having a lot to make up for, if you look at the net tax/welfare situation, the English have been "making up" for it for a while now. But that won't bring prosperity. Why do all the foreign car manufacturers have plants in England and not Scotland? Honda, Nissan, Tata, Toyota, Vauxhall - it's not as if Scotland doesn't have a great heritage of engineers and metal workers. Tata and Vauxhall took over existing facilities - but the Japanese companies built where the best resources were.