In 1994, a few things happened that shifted the balance of power between Country and Top 40 radio. Country, concerned about the possible opportunity for a more gold-based format, started digging deeper in its library again, thus disenfranchising some of the listeners who hadn’t been around long enough to know those songs. It also made Alan Jackson’s “Gone Country” one of the biggest hits of the year. That song was an attack on bandwagon jumping artists and songwriters, but some new Country listeners undoubtedly took it as a shot across the bow, too.

The biggest development, though, was the success of Hootie & the Blowfish, Sheryl Crow, Melissa Etheridge and the first wave of acoustic pop artists who eventually fostered the Modern AC format. Until 1994, it had been Country and Garth Brooks meeting that need for anybody who had grown up with James Taylor and his singer/songwriter friends. Now, Top 40 was full of music that, at another time, might have been exiled to Triple-A.

The new acoustic feel of pop radio was good news for a lot of singer-songwriters, but it left Mary Chapin Carpenter stranded. For the previous five or so years, Carpenter had reeled off a surprising string of folk-flavored Country hits with a lot more edge and gravitas than most of her counterparts. In 1988, Country was the least unlikely place her music could get a mainstream foothold. In 1994, she joined Wynonna to salute “Girls With Guitars.” The following year, as the girls with guitars shifted to the pop side, Carpenter found herself somehow neither Country nor pop (although KALC Denver did try to play her “He Thinks He’ll Keep Her”).

Carpenter finally officially broke ranks with Country radio in the mid-’00s (long after they’d moved on anyway), in “On With The Song,” an album cut that, among other things, took on Country’s treatment of the Dixie Chicks. I hope she’s gotten some satisfaction, however, from the success of Miranda Lambert, whose much different image allowed her to get away with covering, say, John Prine on her albums. The more mainstream “The House That Built Me” was the No. 1 hit that proved that Lambert could do something other than edgy-and-uptempo. But it’s the kind of song that would have, at one time, been the song on a Carpenter album that proved she could sing about more typically Country subject matter.

The other irony is that the girls with guitars are definitely back on the Country side again. Hot AC, taking more of its cues from Mainstream Top 40, has spent more than a decade trying to distance itself from the once-ubiquitous female singer/songwriters. Now it’s Country that offers Taylor Swift (who has this week’s No. 1 Country song with “Sparks Fly”), The Band Perry, Lady Antebellum, who fill the female acoustic need, and don’t have to choose between pop and Country as artists like Carpenter and Rosanne Cash once did.

By contrast, only Colbie Caillat continues to represent the female singer/songwriter at Hot AC, although Kelly Clarkson’s “Mr. Know It All” is a sonic fit with Swift, et al. For the most part, Hot AC fills any acoustic female pop need by borrowing Lady Antebellum, The Band Perry and Swift’s songs six months later, when the country divisions are ready to share them. (You could also argue that Adele is serving a similar purpose, although I think she’s more proxy for Alanis to spurned 16-year-old girls.)

It might seem odd to posit Taylor Swift as anything more than an ironic successor to Mary Chapin Carpenter (or even the Dixie Chicks, whose franchise she also filled in a certain way). But “Bubbly” isn’t exactly “Sunny Came Home” by Shawn Colvin, either. If you like music with that female pop/acoustic timbre, the new, younger-leaning acoustic Country acts are filling that niche. And the Country format that was still struggling with Taylor Swift a few years ago is doing a surprising number of “High School Spirit” concerts this fall and winter.

For all that, the female acoustic sound is still something of an outlier at Country (or Top 40, or any format where it may take hold other than Triple-A). I had noticed recently that my nine-year-old daughter was listening to a lot of Taylor Swift, the Band Perry, Lady Antebellum and “iCarly” co-star-turned-Country act Jennette McCurdy. So on a recent car trip, I put on Country radio to see what would happen. For the most part, the mainstream Country hits didn’t interest her—Brantley Gilbert, Jason Aldean, and even the similarly produced Eli Young Band all flew by. The one that did get her attention, interestingly, was Jake Owen’s recurrent “Barefoot Blue Jean Night.”

But whether you’re listening to Country for Taylor Swift, “Dirt Road Anthem” or Scotty McCreery and Lauren Alaina, it doesn’t seem to matter to the new generation of Country listeners that not every song is for them. And that represents a more significant challenge for Top 40 and Hot AC than even the Country boom of the early ’90s. As anybody who watched the Churban vs. Urban battles of the late ’80s/early ’90s can attest, an incumbent station doesn’t have trouble when its fringe listeners leave; it has trouble when its core listeners decide they like something else. And the latest shift of the female acoustic-pop franchise should definitely inform a format in transition.