User blog:It's Good to be the Queen/Has the Merlin series "jumped the shark"?

For those who are not familiar with the idiom I'm using in the title of this blog, here is the definition from Wikipedia:

"Jumping the shark is an idiom created by Jon Hein that is used to describe the moment in the evolution of a television show when it begins a decline in quality that is beyond recovery. The phrase is also used to refer to a particular scene, episode, or aspect of a show in which the writers use some type of "gimmick" in a desperate attempt to keep viewers' interest."

I bring this up because the quality of the show is being slammed not only here, starting with the blog by Knightofheart about recycled plots, but on other sites. The commentary there is much more colorful.

If I had to choose the moment the show water-skied over an ocean-dwelling predator is with the last one, "A Lesson in Vengance" where several plot devices from several seasons were used in one episode. The gimmick for me was Gwen murdering Tyr while under the influence. I didn't fully understand the reason except for shock value.

A close second is 5 x 05, when Arthur was pondering the Disir's ultimatum, Merlin told Arthur not to bring magic back to Camelot. Again this doesn't make sense; it serves to drag out the secret and frustrate the viewers.

It's getting nuts. I've read fan fiction where the storytelling was well thought out and plotted. If you ask me if the producers want a season 6 they need to fire the current stable of writers and bring in some fresh blood from the fandom.

I would like to know what you think is the moment of the beginning of the decline of Camelot, in terms of writing the series.