While that has indeed been true of many clubs that move to a new stadium, I'm hopeful that Spurs won't suffer the same fate. Unlike so many other clubs to have moved stadium, Spurs won't be making a move directly from an intimate and atmospheric stadium to a much bigger and blander new model. Spurs will be moving from Wembley - the ultimate in big and bland - to a smaller, more intimate and more characterful stadium. No guarantee that form won't suffer, of course, but there's less reason for it to do so.
I can't remember, what happened to City's form when you first moved to the City of Manchester stadium?