Lennon marched onto the pitch to confront Norris about the award of a late Jambos' penalty for handball, which substitute Craig Beattie converted to take Hearts into next month's final against Edinburgh rivals Hibernian.
Dallas, formerly head of referee development at the Scottish Football Association, told STV: "I can't remember in 25 years of refereeing seeing a manager run that far onto a pitch to bully a referee. These pictures are going around the world and it is not good."
Dallas believes Lennon would do well to take note of Tottenham counterpart Harry Redknapp's reaction to the controversial goal awarded to Chelsea on Sunday in their 5-1 FA Cup semi-final defeat at Wembley.
"Take another example yesterday in the Tottenham Hotspur game," Dallas added. "It was a huge occasion and a goal was given where the ball didn't cross the line.
"After the game, Harry Redknapp said he had a chat with the referee, who admitted he made an honest mistake.
"Redknapp said he was disappointed but was keen to move on. That's how we should do it in Scotland."
Source: PA
Source: PA