Under what conditions should one consider trading pitcher Hisashi Iwakuma?

This question arose recently, as rumors circulated that Mariners ownership planned to retain Iwakuma despite interested parties around Major League Baseball inquiring about the right-hander’s services.

Baffled as many fans were that the team would choose to hold onto the veteran starter when a) he will be a free agent at year’s end (meaning the team could sign him in the offseason regardless of where he plays the next two months) and b) he’s been kind of sucky lately, we still find ourselves asking whether dealing Kuma makes sense or not.

Below is a hand-crafted flow chart that should help sort this mess out. (Please click on the image for full resolution.)