The win, the biggest ever inside the Allianz Arena, took Bayern to within three points of clinching the Bundesliga title.
It more than satisfied Heynckes, who had feared his side may not have taken the task so seriously in view of the Champions League quarter-final against Juventus on Tuesday.
"It was important that we carried on the way we have been going in recent weeks and that means that we keep winning our games," said Heynckes after his side's 10th straight Bundesliga win - a new club record.
"It was important for us to tank up on self-confidence.
"We played textbook football at times and we've got to do something similar on Tuesday because we have other objectives for the season."
While Heynckes admitted that the title is now theirs, he spoke with caution about his side's chances in the Champions League.
With Juventus enjoying a similarly successful season in Serie A, with a nine-point lead at the top, Heynckes has warned not to expect them to roll over in the same way Hamburg did.
"It's going to be a completely different game on Tuesday," he said. "Juventus are a top European side who are aggressive and run a lot."