I stepped back from regular reviews of "Smash" after last week's episode, but in watching Monday's, I couldn't help marveling at how most of the hour felt like Theresa Rebeck wrote it on a dare to prominently include every one of the most hated characters and stories the show has developed in its short, uneven life. Particularly amusing, but not in the way intentioned, was that we actually took several minutes to revisit the legal troubles of Julia's son Leo, who's not only incredibly irritating but has nothing to do with the show within the show. At least when we spend time with the horrible Ellis, it's within the context of making "Marilyn: the Musical," or whatever it's going to be called; why exactly are we spending time with Leo, who's part of a plague of Annoying Teenage Boys who have descended on television in the last few years?

While I was musing on that yesterday, "The Shield" creator (and producer of "Terriers," "The Unit," "The Chicago Code," etc.) Shawn Ryan was going on a Twitter run about all the ways "Smash" had gone awry, and suggested that at least some of the problems had to be coming from network notes. I asked whether we could blame networks for all the obnoxious teenage characters — not just Leo, but Tyler on "V," Jack Linden on "The Killing" and Josh from "Terra Nova," to name three recent examples — and he said yes, then tweeted, "Think a lot of writers/networks mistakingly think the mere presence of a teenager is show (however annoying) will lure teens into watching."

And that's not a new phenomenon, nor one that's confined to adult programs. I remember when I was a kid, a lot of the cartoons I watched had kid characters — often, in the case of something like "Superfriends," adding them to pre-existing source material where they didn't exist — who were elevated to a position of prominence that never made sense to me at the time. With the benefit of hindsight, I have to agree with Shawn's theory, and say they were there because an executive or producer assumed kids wouldn't want to watch a bunch of grown-ups have adventures unless there was someone close to their own age to relate to. And it always seemed like a fundamental misunderstanding of the audience. Though some of the kids were non-terrible, I was tuning in to watch Superman or Batman or the guys from M.A.S.K. do something cool, not Wendy and Marvin, the Wonder Twins or Scott Trakker and his pet robot T-Bob. Or, to use a live-action example from when I was slightly older, think of Wesley Crusher, who was there as young audience bait, and yet is someone whom Wil Wheaton is still apologizing for 25 years later.

For similar reasons, I don't think anyone's not going to watch a show about the making of a Broadway musical, or the investigation into a murder in Seattle, or the forming of a rebellion against an alien invasion because there's not a character their age on there. You're going to watch or not watch because you're interested in the subject. And yet time and again, we get these younger characters shoe-horned into genre pieces, and the great majority of them are unwatchable. It's like everyone involved thought they just had to cast someone young-looking and get back to focusing on more important matters.

That's not to say that there aren't plenty of good teen characters of either gender on television. Just watch "Parenthood" (or, before it, "Friday Night Lights") to see how well it can be done. But usually, these characters work because the show is designed to be as much about their concerns as the adults', rather than sticking them in at the last minute to hit some kind of demographic sweet spot. I've mentioned how compelling Rex on "Awake" is, which is a credit to Dylan Minnette's performance and the writing for the character, but that's also a show that couldn't exist without Rex; he's as necessary to everything as Britten's wife, his two partners, the cases, the shrinks, etc.

(It's funny that both "Awake" and "Homeland" — which I thought (though others disagreed) did a very good job of integrating Brody's daughter into the story and making her central to its resolution — are produced by Howard Gordon, who was also one of the key writers on "24," which had the female equivalent of this problem in the perpetually-endangered Kim Bauer. At least there, they recognized after a few seasons that it was getting silly even by their standards and wrote Kim out.)

The kid characters on "Game of Thrones" are all very strong — and when you despise one of them, like Joffrey, it's because you're supposed to, and not because the writers and actors have fallen down on the job — but that's also a show working off of source material where those characters existed, and I think it's safe to say that George R.R. Martin wasn't trying to cover as many demographic bases as possible when he conceived of all the characters in Westeros.

And there are some exceptions even to the idea of a teen boy character on a show where he's not really necessary, like Noah Wyle's oldest son Hal on "Falling Skies." Whatever problems that show had as it moved on, Hal was never treated as an idiot plot device like Tyler or Josh, or a whiny brat of variable age like Leo. He didn't do everything perfectly, but he also doesn't get into trouble just to generate story, and he's written consistently. Not the show's greatest asset, but also not it's hugest liability the way a bunch of these other teen boys are.

It's gotten so bad that on our recent podcast review of "Missing" — where the teen character is baked into the premise (remember, Ashely Judd is a MOTHER, looking for HER SON!) — Dan and I actually felt the need to stop and discuss where Judd's son fit on the Annoying Teenage Boy continuum. (My feeling was that he gets worse the more he's given to do, which is generally not a good sign.) And Shawn, who's currently at work on the "Last Resort" pilot for ABC, felt the need to remind his Twitter followers that this show will not feature any characters like that.

He's not the only creator developing a pilot right now. There are dozens and dozens of drama and comedy pilots being shot and edited right now, and depending on which ones get picked up, we could face another wave of noxious, unnecessary, badly-written and/or performed underage characters coming our way in the fall. I'd like to think that the failure of "Terra Nova" (which was, after all, supposed to focus on the family), the "Smash" audience's unrelenting hatred and mockery of Leo, etc., might convince producers and network suits that the new shows either need to do much better by their teen characters or else would be much better off without them, but I doubt it. I've seen too many Zan and Jaynas, too many Wesleys and (to borrow someone from the other gender) Kim Bauers to think we're going to be rid of this phenomenon anytime soon. All we can really hope for is that the casting and writing gets better over time, but if not, we're going to get more moments like Leo moaning like a 9-year-old, "My sister is waiting for us in China! What is going to happen to her if we don't go and get her!"

What does everybody else think? What, to your mind, separates the good kids on adult shows from the bad?

Alan Sepinwall may be reached at sepinwall@hitfix.com