This is true. Once you have a publisher, the publisher has been assigned Administration Rights and things could get messy if you are the songwriter and you try to refuse a licence. Songwriters who self-publish will always have the right of refusal, but publishers are the ones that do all the work to exploit the music catalog. Typically, they get to take 50% of what the song earns through licencing and they are not going to be happy if some whiny songwriter says “but I don’t wanna have my song in an underwear commercial!”
On the other hand, if the scene in the movie is extreme enough, even the publisher might get nervous about damaging the music’s future marketability. But most of the time, if the song is going to be used in a “memorable” way, that’s rarely a bad thing.
And… CORRECTION: (Hey, it’s been eight years since I was working as a lackey at my ex-girlfriend’s) – the film and TV people need the Synch Licence and Master Use Licence. A Performance Licence is a different animal: it’s for the commercial broadcast or performance. I think I conflated it at first with the Master Use licence, but didn’t figure that out until I was on my bike in the middle of nowhere.
ASCAP, Harry Fox, et al. are music rights organizations. They are the associations who take care of royalty payments to the songwriters (or copyright owners if the rights have been transferred) from any income derived from the composition, usually thorugh performance rights or records sales. There are accounting and reporting procedures so that when a CD is sold or when the song is played on the radio or TV (radios are supposed to submit playlists), the songwriter gets his or her share which is held in escrow by the rights association and paid… um, quarterly, I think. I don’t remember the payment schedule.
I also don’t know how the reporting procedure works for legal downloads, but I assume it’s similar to record sales.
The performing rights guys are also the ones you can get a Mechanical Licence from if you are a band doing a cover tune. Since the Mechanical Licence is compulsory (sonwriter and publisher can’t say “no”), there is a fixed rate for licencing a song. The Statutory Rate is currently 9.10 cents a song PER COPY (for songs up to five minutes long. Longer songs are more expensive). So if you sold 10,000 CDs with that one cover tune, you’d shell out $910 which would be collected as royalites by the music rights association, who would then pass it along to the songwriter/copyright owner.
For indie bands and community groups that are only doing really small pressings (making only 2,500 CDs or less) you can just get the mechanical licence online and it’s not prohibitively expensive unless you’re in a band made up of non-income generating teenagers.
Remember the Mechanical Licence is only a licence to use the music on a recordign. Once it becomes audio-visual like a movie, then it’s a different medium requiring Synch Licences and Master Use Licences. Those two are paid in full to the songwriter/publisher at the time the contracts are executed. The musicians rights associations don’t deal with those. They deal with mechanical and performance royalties.
ETA: As for how much of a song is controlled by artists, that depends on a long of long-winded negotiating in recording contracts and with your publisher, and if there is more than one composer.