shoemaker put up less than replacement level fWAR all but one of the last 5 years. He was seen as bad. Happ was seen as ok to bad, not bad, I guess. But, a contending team can't give up one start position, and have another filled by a number 4, and expect to be great, imo. I'm ok if you disagree.
Really, Shoemaker had not been productive but once in the last 5 years.