Interestingly, TG do not seem confident in premium yields from ARN/CPH and have opted to sell half the business seats as premium economy. I always thought the TG premium economy was only a stop gap measure due to the old 747 All Series product.
They will have to adjust their current pricing strategy if they expect people to pay for C. The only difference with C now is service, food and lounge access (assuming cabin size is the same)