F ootball, it transpires, is not rocket science. If it were, Nottingham Forest would not be close to securing Premier League survival and two games from Champions League football next season. The club’s approach could hardly be described as methodical but whether by accident or design, Vítor Pereira, Forest’s fourth head coach in six months, has found the right formula. When eight changes to the lineup were announced for Monday’s visit to Chelsea , eyebrows were raised as the second string were sent out. It allowed Pereira to rest others for Thursday’s Europa League semi-final second leg at Aston Villa. Within two minutes they were ahead and by the hour they were out of sight and a further step towards salvation thanks to a third away win in a row. Others will point to different significant victories but the one at Stamford Bridge showed Pereira has everyone in the squad firing.…