:::I think my edit, and the one about "Patton the one episode wonder", should either both stay or both go. But with Dean Winters... yeah you're right. He was mentioned because an interesting piece of information about his addition to the show was available. And if you mention some one joining the show, you might as well mention him leaving the show. By that logic, would my edit be more welcome if I find some story about the first appearance of Merlin and/or Hermann and/or Fuente in a reliable source? 

 As for original research, my gut tells me that Leight's takeover was precisely the cause, even though I didn't directly say this. That's why there has never been another SVU season when a recurring character was absent for the first time in 9 seasons, much less three. What if I were to cite the quotation where Warren Leight found TARU scenes boring and hired Gilbert Gottfried to spice things up? I think that would be enough to link the sudden absence to the new showrunner for one of those actors.