I agree. This sort of airspace & the prevailing traffic levels cannot be controlled procedurally. End of story !
Apart from anything else, how on earth can Controllers remain proficient Procedurally when the traffic loading is too high to allow them to operate Procedurally ? And, how can they "slip into Procedural Mode" when the Radar that, alone, is enabling them to separate & handle that heavy level of traffic suddenly presents them with what is a frightening emergency situation ?