By the end of this rout, the home fans were chanting "we're Man United, we'll do what we want", which was pretty much anything against supine Schalke in reaching the Champions League final.
The M1 will probably prove more troublesome for United in getting to Wembley than the guileless Germans did.
Barcelona, the team of all the talents, will be far less accommodating than Schalke on May 28. Pep Guardiola, who travelled to Old Trafford last night to watch a largely second-string United, will send out such stars as Lionel Messi, Andres Iniesta and Xavi.
La Liga's finest will be the favourites, with box-office billing also going to the defensive likes of Gerard Pique and the attacking right-back Dani Alves.
But nobody, certainly not the respectful Guardiola, will dismiss United's chances. There is a belief to United, a refusal to bow to adversity that gives them a chance. They also have a desire to make amends for their Rome defeat to Barcelona two years ago.
United will take heart from picking up no suspensions here and no injuries, although Patrice Evra was briefly hobbling. Ferguson will also delight in being able to make nine changes, keeping making most of his first choices fresh for Sunday's meeting with Chelsea.
Even without the likes of Wayne Rooney and Javier Hernandez, United scored through Antonio Valencia, Darron Gibson and Anderson twice.
Ferguson also welcomed back Darren Fletcher, who United will need to get to grips with Barcelona's fabled midfield.
United had this tie in a stranglehold from Gelsenkirchen and never loosened their grip, tightening it particularly after 26 minutes.
In front of the watching Guardiola, Valencia drove United closer to the Wembley final against the Catalans.
His goal was a gem, a riposte to Barcelona's classy move that led to Pedro's strike the night before against Real Madrid.
When Uchida lost possession, Anderson pounced and United raced through the gears. No matter the changes, this was classic United, going for the opponents' jugular. The B-team responded with the alacrity of the A-team, tearing Schalke to little dark-blue ribbons.
Anderson found Gibson, whose ball to Valencia carried echoes of Andres Iniesta's sumptuous pass to Pedro. It was a majestic delivery, completely destroying Schalke's defence. Valencia, gliding down the inside-right channel, needed only one touch to tee up the ball before beating Manuel Neuer with a firm shot.
Already leading 2-0 from the first leg, Valencia's goal seemed to have swept United over the horizon and halfway up Wembley Way. Within five minutes, Ferguson's men led 4-0 on aggregate, although the goal was still a surprise.
Gibson has an eye for the long-range strike, although many United fans have often wondered whether he would develop into a top-class midfielder. Too diffident at times, but not here.
The Irishman certainly seized his chance. Following Rafael's throw-in, Anderson and Valencia worked the ball to Gibson, who met it first time. The shot arrowed straight at Neuer, whose excellence in the first leg was hailed by Ferguson "as probably the best goalkeeping performance against us in Europe".
Not here. Not when Gibson came calling. This was more Manuel than Neuer. The German international 'keeper spilled the ball, which bounced in off the post.
There was almost a gasp of disbelief that such a good 'keeper could make such a mistake. Then United fans let rip in celebration, knowing a third final in four years was all but theirs.
Any early fears were dispelled. Ferguson's tactics had been vindicated, his team-sheet making total sense. Ferguson had admitted that his centre-halves, Chris Smalling and Jonny Evans, "lack the experience of big-time situations" and they were up against Raul, the leading scorer in the history of the Champions League.
Raul certainly never troubled them before the break, partly because the service was poor, and it was little surprise to find him supported by Edu in the second half.
Before then Smalling had dealt well with Raul, tracking the former Real Madrid striker's first run, hooking the ball away. Smalling then darted in ahead of Raul, who was operating as the forward point of Schalke's 4-2-3-1 system.
Ferguson's much-changed team-sheet had spread ripples of concern through United's support, who were at least reassured by the sight of Javier Hernandez, Michael Owen and Ryan Giggs warming up after 10 minutes.
Up in the stands, Wayne Rooney and Rio Ferdinand looked on, admiring the goals of Valencia and Gibson.
Smalling's only mistake of the half came 10 minutes from the break, being loose with a clearance, and was brutally punished. Jose Manuel Jurado drilled the ball into net -- deserved reward as the midfielder had looked Schalke's best source of hope.
Schalke fans started chanting "only three more". Far less amusing were the brief scenes of trouble in the front two rows of the Schalke support, which subsided only when the police eventually arrived.
Flares were lit, a plastic bottle thrown, and Uefa may have a word with Schalke after this.
It was merely a disappointing sub-plot to the main drama at the Theatre of Dreams. As the second half unfolded, the Stretford End went through their song-book, praising Ronaldo, Cantona and Rooney and chanting "we're going to Wembley".
Still the singing continued, this time about Paul Scholes, who already had his obligatory booking. They also sang of Nicky Butt -- who played in the 1999 final while Scholes and Roy Keane missed out -- and Bryan Robson, enjoying their stroll down memory lane.
Then it was Andy Cole, celebrating his goalscoring. They then almost celebrated an unlikely goalscorer, Smalling turning the ball into the net after 70 minutes but being ruled offside.
No matter. As Guardiola continued to watch, United grabbed a third after 72 minutes.
Nani was the architect, racing down the left, and cutting the ball back to Anderson.
The Brazilian collected the ball at the second attempt, and fired it low and left-footed past the sluggish Neuer.
There was more, much to the delight of Old Trafford. Valencia released Berbatov down the right and his low cross was turned in by Anderson. (© Daily Telegraph, London)
Whatever the improbability of failing to negotiate this tie, Alex Ferguson rolled the dice last night. No doubt about it. Even approaching 70, the Manchester United manager still has the capacity to surprise, to take a risk.