Tottenham has always had a London postcode and fallen within the jurisdiction of London County Council (precursor of the GLC and now the London Assembly) - pre 1947, I think it was known as Tottenham, London N - no post codes back in them days. When the Post Office divvied up London as it expanded post war, those N, S, E and W postal addresses added numbers and letters to aid mail delivery. In fact "S" disappeared completely and was shunted off to Sheffield replaced with SW and SE. Tottenham has never been part of Middlesex's jurisdiction though rumour has it that we fielded 2nd XI teams in the Middlesex Senior Cup in the late 1800's. Parts of Edmonton have been in Middx and everything north of the historic A406 boundary were. Middlesex, as county council ceased to really exist even before 1965 with the key big towns in the old county (Hounslow, Enfield, Brentford, Wembley, Hillingdon etc) being absorbed into London Boroughs.
Any Goon clinging on to this as a valid reason to debunk their franchise origins is even sadder than the rest of them.
From an ex - Post Office worker!