Nick Lachey has called taking part in the Newlyweds reality show with ex-wife Jessica Simpson one of dumbest ideas he’s ever had.

Nick appeared on The Late Show with David Letterman on Wednesday and when Letterman said he thought the show would have strengthened their relationship, Nick replied: “About that. Not so much. I don’t think so… it was among the dumber ideas I think I’ve ever seen executed in history.”

“For a while, I think we actually enjoyed doing the show as well. It was just so invasive that it became a problem.”

Letterman asked if Nick thought the show contributed to Nick and Jessica’s split and eventual divorce, Nick was less sure: “You know that’s one of those things where I think until you get enough hindsight and enough clarity and perspective, I don’t think you can really know what happened. But, I certainly think it was probably a factor.”

“I think both of us have handled it about as well as we possibly could, under the microscope that we’re under and everything. But, I think, again, with time, it’ll give us a better opportunity to redefine our relationship.”