I see what you are saying but also bear in mind that a TC approach controller could be cross valid at HI with any other and so this reduces the overall number of controllers required as they can chop and change to cover other airports as they do now between SS and KK for instance. Don't tell me that solent approach is less busy than Luton and they do that at TC (read any good books lately lads ?). Lots of Thames radar controllers knocking around TC looking for another validation. Bums already on seats. I'm sure that the overriding vision would see all our airports tower only with all approach functions carried out by the happy families at the centres.
We will see..............