It would though because Watford haven't sold out, so there'd be empty seats, and the sunderland fans would only be allowed so far across before they'd need segregation of access tunnels, the concourse, turnstiles, toilets etc... You can't just jam 800 Watford fans into 800 seats and sell every other seat to home fans. They'd need full blocks left out, so maybe 1200 or 1400 seats for 800 away fans.
It makes a difference, why have us attacking an end with empty seats and scattered away fans when we can attack both ends all game with 100% sunderland fans behind them and to the sides with no away fans and no empty seats. It's defeatist. Stick the Watford fans up top out of the way and squeeze them into the blocks closest to the end of the north upper and keep selling the empty seats to our fans. Any empty seats in the ground should only be in the north upper