Really! Everything in sight! You must be very old! Because the pattern below does not support the idea of Spurs winning everything in sight before 1971 and Arsenal been a mid table team compared to Spurs see below. I would say there never has been a north London power shift as it only exists in the minds of HIAG and other Spurs supporters like him. One could say Arsenal took a breather and Spurs won couple of league titles by the looks of the pattern



Spurs:
First division/premier league winners 2, 1950-51 and 1960-61
Arsenal:
First division/premier league 13: 1930-31 1932-33 1933-34 1934-35 1937-38 1947-48 1952-53 1970-71 1988-89 1990-91 1997-98 2001-02 2003-4