This notion of it creating just £10 million is just a cautious estimate I should think. Think about it.
If you ignore the executive boxes and just say 10,000 extra seats then that alone would bring in around £6 million a season just for those without any pies and beers on top. If you assume that because the new stadium won't be a [Poor language removed] hole with restricted views and decaying toilets you might find average ticket prices rise to reflect the better conditions. That would add a good few million to things.
Then you have the exec boxes, which considering they go for a few thousand per game will bring in a hefty sum. Will sponsorship of the new ground go up or down? I'd be amazed if it went down and it will quite probably go up. Retailing/catering concessions, better or worse than at Goodison? Again, surely that's some extra revenue both from retailers and supporters.
You see where we're going here? In business it's quite common to use scenarios when planning and I dare say Wyness is giving you lot the worst case scenario because you're such a bunch of moaning minnies