It's January: Time to Kill Off the Third Wheel

Is there some Hollywood calculus that determines that just after the mid-season break is the right time to kill off the hero's love interest's law enforcement fiancé?

I began to wonder as I watched two untimely, brutally violent, but romantically necessary deaths on Friday's back-to-back episodes of Flash Gordon and Moonlight.

For the how and why, not to mention my starling admission that I'm actually starting to look forward to Flash Gordon, see the attached article.