Skipness, your posts are usually pretty balanced and informative however you do yourself no favours with comments like..."Perhaps your fab, new Republic will change all that.." Uncalled for. In terms of the three airports, as SLF I use all three on a fairly regular basis for business and my obervations (no data to hand) are that:
Edinburgh: Business , In-bound Tourists and then Holidaying Scots in that order.
Glasgow: Business, Holidaying Scots and in-bound tourists.
Prestwick: Holidaying Scots equal to in bound tourists and then business way behind.
I would be really interested in the % breakdowns for each airport.