Meaning that the worst thing a radio station could do would be to turn off listeners and have them reach for the change button.
"What you want to do is build an audience," Allen says. "What many programmers do in country is test the music that they plan to put on the air. They only air music that tests favorably."
The key is "to not explain why you're putting something on, but fit the general (sound) that the listener has come to expect."
WKDF's Kelly says, "My job is to generate ratings, not album sales. If something is generating album sales, it's something I've got to look at."
"There could be records that could be successful for the record labels that don't work for mainstream radio," Kelly says. "We are two completely different industries that work in tandem for the exposure of artists, but sometimes don't (meet)."
Of course, radio stations also will say they are playing a particular song because it does sound different. A recent example of that was Mark McGuinn's hit out of left field last year "Mrs. Steven Rudy."
In the wake of "O Brother," what lies ahead? Country music has been waiting for something to jump start sales for several years. Once the line dance fad went bust about five years ago and the hat acts faded, country also saw its sales decrease. The number of radio stations dipped from about 2,300 to 2,100, according to Allen, but is remaining steady.
Could "O Brother" bust the doors open to a different kind of country hitting the airwaves?
Not a likely scenario.
"I don't see much effect," says Bob Duchesne, operations manager for Cumulus Broadcasting in Bangor, Maine, who oversees programming and marketing for five stations in that area.
"I've been in country music long enough to have been through the pop and traditional swings. So, I suppose one big question is would 'O Brother' be the engine that gets country back on a more traditional style the way that Ricky Skaggs did in the '80s and Randy Travis did in '86. I think the answer is probably no."
"I think an awful lot of people who are into roots music as anything else that got into the album," Duchesne says. "As far as the hardcore country listeners, I don't think it affected their taste in country music very much."
"I think it appealed to a very broad group of people only part of which are country's target for a group," he says.
In fact, the label that released the album, Lost Highway, also the home of folks like Lucinda Williams and Kim Richey, is not gearing itself to country radio at all. In fact, they seem to be going more after the NPR crowd - in other words, a bit older, more highly educated and better off than the typical country crowd.
Country radio tends to focus on young female adults.
Another factor pointed out by Duchesne is that labels have grown increasingly constricted. Some folded or were taken over by others (Warner, for example, took over Giant and Atlantic).
The result has been fewer artists on labels and record labels trying for the hit to get their act on the airwaves.
"I think some of the signs to watch for are how are some of the more traditional (acts do)?" says Duchesne. "Does Willie Nelson do well with 'Medocino County Line'? Does Brad Paisley become huge? Kevin Denney? Will one of those traditional artists break through and become big?"
"It could show a swing coming.," Duchense said. "Because sooner or later, it does swing. This swing seems to be taking a long time to get here."
Rounder's Irwin says he forsees some positives coming out of "O Brother," although not necessarily on regular radio station playlists. "We're seeing me of the syndicated bluegrass radio shows being picked up by country stations," he says. "These are country stations that wouldn't be playing 'O Brother,' but have picked up some of the syndicated shows."
And bluegrass could also benefit from Country Music Television, according to Irwin.
A few months ago, CMT had "Bluegrass Week," where they focused on bluegrass. "They got over 7 million viewers, and they were just shocked," says Irwin. "They also let it be known that they would be open to having some bluegrass videos."
"They'd already been doing Dolly and Patty Loveless and Alison (Krauss) and Nickel Creek. They were interested in seeing some other people who had been doing bluegrass full time rather than touching it.
The beneficiaries of the soundtrack seem to be folks like Ralph Stanley, who in his mid-70's, may be attracting a wider audience than ever.
Miles of Music, a Los Angeles area mail order business generally for very hard-to-find independent country and roots music releases, saw sales of Stanley go "up significantly," according to Jeff Weiss, an owner of Miles of Music. "His titles are selling more broadly for us."
"Emmylou's a constant seller for us. Alison. Certainly Dan Tyminski (the voice of George Clooney in the movie's songs) benefitted from us. It didn't seem to resonate with people until they bought the CD. Then sales picked up for it."
MOM sold one or two copies of Tyminski's Doobie Shea solo debut before the soundtrack took off and about 50 after that.
Tower's Kerlikowske says, "Where 'O Brother' has opened things up, is people who have not been exposed before, especially younger people. It's amazing how many younger people are coming in and listening. The biggest benefactor even though they weren't on the record was Nickel Creek. For Chris Thile (a member of the youthful trio that has done boffo numbers), the two previous to that, it didn't do much of anything. But this one is a smash."
But he discounted the effect of "O Brother" on country.
"Unfortunately, I think it's going to be a one-hit wonder, but you never know," says Kerlikowske. "It's going to have something else to drive it other than the music itself for people to make a connection. Whether it's another movie or a documentary."
"It's such a phenomenon. It's like Michael Jackson trying to do 'Thriller' again. It's not going to happen."
"I don't think anyone has yet to figured out how to grab onto the coattail and make something from it. They've done 'Down From the Mountain' and 'O Sister,' (a Rounder compilation of female bluegrassers that has sold 70,000 copies) but I don't think they've figured out yet how to capitalize on this phenomenon."