The boss was hurt by losing the Barclays Premier League on goal difference last term and vowed it would never happen again. Even with a healthy 12-point lead in the table, and with a 10-goal advantage on closest challengers Manchester City, a ruthless approach is still being preached.
Speaking in his Inside United column ahead of the last league outing, a 4-0 thumping of Norwich that suggests the message is getting through, Sir Alex was demanding more goals.
When asked if United have still to hit top gear, despite sitting top of the league, he replied: "You might be right. Where I think we can improve is that we don't seem to kill teams off.
"We've beaten Wigan 4-0 on two occasions but those are the only matches we've won by that sort of margin [ahead of the Norwich clash]. In a normal season, I'd expect a few more wins by that sort of distance. Last year, we won 5-0 against Wolves, Wigan, Bolton and Fulham, and we beat Arsenal 8-2, of course.
"We're not seeing those results this season, however. We haven't hit those heights. Hopefully, there's more to come and we'll discover that killer instinct that our teams in the past have had."