I guess the reality is a lot of larger companies need to be inside the eu. If on the day Scotland finally leaves the uk, they join instantly the eu, then this would be fine, unfortunately, whatever the yes campaign say, the legal situation looks different.
At the point of a yes vote, businesses in Scotland have about a year before independence happens, so do they use that to move, or do they sit tight with confidence that salmond can deliver eu membership for them.
And yes, the financial institutions will have to move hq to the uk.
The reality is, iScotland will be ok in the long term, but it'll hurt in the very short term (say the first 2-3 years), and the mid-short term (first 10-15 years) they'll be worse off than if they were still in the uk, that doesn't mean financial melt down, just a bit poorer, fewer jobs about, less stable.
If you are in a position to ride out that first decade, then a yes vote might not be that bad.
Pretending it'll be smooth from day 1 might get more over to the yes vote, but when it bites, the SNP are going to be slaughtered in elections.
There doesn't seem to be a ground swell of "yes it'll hurt, but we want self determination" - people are more likely to accept cuts and unemployment if they know it is coming.
Long term, it'll be fine. Possibly even great. Short term, it'll hurt, admitting that isn't a bad thing.