The criticism came following the decision to scrap the £15million project after a shortlist of six schemes was drawn up and a panel of judges selected the entry by Glasgow-born architect John McAslan.
However, within minutes of the announcement being made, council leader Gordon Matheson said plans for a major refurbishment of the area had been scrapped.
Instead, the council's executive committee was this week asked to agree that officials come back with alternative proposals. They will involve keeping the statues, improving the grass areas and replacing the unpopular red surface.
But Mr Henry said the project was like something from the Carry On comedy films.
He said: "This is a lesson for the council on how to mishandle things. It could be described as Carry On Council.
"We agree George Square needs refurbished because the red Tarmac is not a reflection of the city. But people did not like the lack of consultation, the removal of the statues and the lack of green space. There was not a desire for this massive redesign and complete overhaul.
"Some serious mistakes have been made in terms of the £100,000 the council spent on this."
Opponents of the plan had suggested the public should have been widely consulted on the winning scheme by Mr McAslan in the same way the people of Aberdeen were consulted on plans to revamp Union Terrace Gardens in the centre of the city.
But Mr Matheson said: "I am aware the SNP group's view was to have a referendum following the example of Aberdeen, but that cost £250,000.
"In Glasgow, the cost would have been well in excess of £500,000 and the administration did not support that.
"The administration has listened to the views of the people of Glasgow that emerged during this robust process.
"What became clear during that process, and in particular once the six designs were made public, was there is no consensus in favour of a radical redesign of George Square.
"The choice is to drive on with the view of the judging panel or to listen to the people. The decision of this administration is to listen to the people.
"We will be bringing forward proposals for a substantial facelift and investment in George Square.
"During this process there has been criticism of this council for not listening to the people. Now we are being criticised for listening to the people."