Hi Jabird,
Not sure that the Solent analogy is applicable (and putting aside that net disposable income per head in the area is probably rather more than Tees Valley). SOU is a performance restricted field so if the FR's want to operate fully loaded 738s in and out of the region, BOH is the only option. SOU is also rather restricted in Apron space and gate size, which again pushes the larger acraft locos to BOH. If SOU had a longer runway and larger terminal development space, I'm sure that BOH would look more like MME