Sunday’s win, secured by goals from Wayne Rooney, Juan Mata and Robin van Persie, was United’s sixth in a row and galvanised their grip on third place in the table, but there were rough edges to the hosts’ display.
Liverpool created a host of chances, with David de Gea earning the man-of-the-match award for a series of spectacular saves, while Mata’s goal should have been ruled out for offside.
It had been a similar story last Monday when United won 2-1 at Southampton despite registering only three attempts at goal.
But van Gaal believes that United are now a different team to the one that slithered to a seventh-place finish last season following their travails under his hapless predecessor, David Moyes.
Asked for the secret to United’s current form, the decorated Dutch coach told his post-match press conference: “Because we have a way of playing that always takes into account the qualities of the opponent.
“I have a staff that always are looking for the way we can do pain to the opponent. And we found this today (Sunday) again.
“It’s not for nothing that we scored the way we have scored today. You need luck, but you can force the luck, and we are forcing the luck now. That was not the case at the start.”
Rooney, who played in midfield, set United on their way in the 12th minute by sweeping home a cut-back from Antonio Valencia.
Mata headed home five minutes before half-time — a goal described with some justification by Liverpool manager Brendan Rodgers as “clearly offside” — and then teed up van Persie for United’s third in the 71st minute.
– ‘Recapture the team ethos’ –
An injury to Marcos Rojo obliged van Gaal to deploy midfielder Michael Carrick as one of three centre-backs in a defensive set-up that mirrored Liverpool’s.
The visitors regularly found a way in behind United’s defence, with De Gea thwarting Raheem Sterling and substitute Mario Balotelli three times each, but van Gaal felt his players adapted well to the enforced changes.
“Only yesterday (Saturday), Rojo in a training session got injured and then I have to change my line-up again, which I have to do every week,” he said.
“But the most important thing is my philosophy and when you stick by your philosophy, every player can do that because every player has played already in that philosophy.”
Defeat completed a miserable few days for Liverpool, who were knocked out of the Champions League by Basel last Tuesday and now trail United by 10 points.
Rodgers admitted that his squad had lost some of the team spirit that saw them come within a whisker of pipping Manchester City to the title last season.
“For me, the whole scenario is about looking to build a team again,” said the Northern Irishman, who lost Luis Suarez to Barcelona in the close season and is currently without striker Daniel Sturridge due to injury.
“We had a team that was growing for a couple of years that has changed now, the squad and injuries and whatnot.
“But we’re having to recapture the team ethos again and that’s something we’re looking to build towards.”
Rodgers sprang a surprise by dropping goalkeeper Simon Mignolet, whose form has come under scrutiny, and he confirmed that Australian Brad Jones would remain in goal for Wednesday’s League Cup quarter-final at Bournemouth.
“Simon has been fine. He’s a really good professional. I spoke to him the other day and he accepted it,” said Rodgers.
“I said to Simon it was for an indefinite period. He has played in a lot of games, Simon, and Brad in my first year came in and did very well.
“It is something that can happen to keepers, taking them out of the firing line and giving them time to reflect.”