That 12 game run included 11 games against teams in the top 9. When Roy took over he had one game against the top 9 (they lost). I think most of us fully expected Vieira would have picked up the wins that Roy did once they got past that horrid run of fixtures.
If we're only looking at premier league games, Newcastle, Man U and Bournemouth this season were three consecutive wins (there was a europa league loss between Man U and Bournemouth)