When Enfatico announced last week that it would break apart the firm, the decision seemed to validate industry skeptics who speculated the all-in-one agency experiment was doomed from the start. The PR division will now be housed under fellow WPP firm AxiCom/Cohn & Wolfe Group, while advertising and other disciplines were moved into various Young & Rubicam Brands.

The project first stunned the marketing world when in 2007 Dell hired WPP to co-create an agency that would provide all of its ...