Thanks for the link to the very insightful interview! I figured that Mark wasn't as popular as Dane, which is why he was killed off, but it's interesting to learn that it was partially Mark's decision. While I preferred Dane I think Mark also did a good job, and I think Mark worked better with Kelly than her next boyfriend Nick did.
Even if I also liked Mark Arnold as Joe, I think it wasn't the case of all the SB fans then. The recast didn't completely work. So that's why the producers decided to let Joe disappear and to offer... more