It is but you wonder what the club found out with the work they did do when they, apparently, seriously considered expansion before deciding against it. It surely wouldn't be too difficult to get a decent estimate of demand using the ticket data they have, market research they did and using comparison with other clubs.
Corporate and hospitality income seems to be the thing that makes the big difference. I've always compared our potential income with Swansea, Hull, West Brom etc. but you wonder if a southern club had greater potential for corporate income. Brighton and Southampton generate a lot per fan, presumably due to south prawn sandwich types. AFCB must have a fairly decent idea of potential income.