In fact, it was only Connacht's second victory over their Irish rivals in 21 attempts and the first time that Lam had actually got the better of Ulster as head coach.
And he believes the determination his side showed in quelling an Ulster fightback - the visitors scored 17 second-half points to Connacht's eight - is cause to be optimistic.
"It's a monkey off my back," said Lam. "We've beaten all 11 teams now, so I'm pleased. It gives us belief, we've only had five games and we've got a few to go, but it's a great build-up to next week.
"We showed character, we'd such a horrendous, disruptive week. We named a team on Monday, but it completely changed by the Captain's run.
"We have our system, but the culture is what we're about. What carried us through was culture and belief."
Connacht showed signs of the team that claimed the title back in May during the bonus-point win - their second in succession after a 28-15 defeat of Edinburgh the week before.
But Lam insists he is going to demand more of his players after witnessing a number of chances to put the game to bed go begging.
"When we're going well we need to put the foot on the pedal and we didn't," he added.
"There was a couple of system errors, a couple of things that didn't go right, but it was all about whoever had possession in the right areas of the field and put the pressure on.
"To get back-to-back wins is a credit to the mindset and the attitude."
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