It seemed the stage was an unnatural situation for Jack to be in.
The show opens with cabaret dances and Jack announcing that it's "show business". Indeed, it is show business and it's a tough gig.
As Jack shouts out his punch lines, cutting through the awkwardness of his stage presence as he quickly transitions onto the next joke. His irony, wit, epiphanies, etc. were juvenile and lacking.
I like Jack, 'Travel with my Father' was entertaining though at times Jack's behaviour was cringe worthy.
Bottom line, Jack is not a good story teller.