"The south of England benefits greatly from all sorts of public expenditure (particularly in London), Crossrail, sewers, Heathrow, Thames Barrier etc etc - which are paid for out of general taxation from all of us, North and South."
Well, let's look at some facts, shall we?
In the 2015/2016 tax year, every Londoner provided £3,070 more in tax revenues than he or she received in public spending, while people living in the south-east ran a surplus of £1,670 per head.
Tax receipts per head in London of £15,750 were almost double those in the north-east region where each person contributed £8,200. As far as public spending goes, it was actually greater per head than tax receipts in every UK region except London, the south-east and the east of England.
Put simply, London and the South East subsidises the rest of the UK. There are reasons for it of course - the City of London finance sector being the main one - but it might be better to check the facts before making sweeping statements about who pays for what.