Hey Dave....Good Stuff....I can see writing a melody to somebody's words but sometimes that has been awful as they keep rejecting my melody so I just told them to stuff it. It became SO Tedious that I couldn't stand it.
Writing words with somebody else is also not good for ME because it loses focus....I tried that once and my words and style and his words and style didn't sound like they went together. I've tried giving my stand alone melodies to lyricists and nobody seems to be able to do that.

SO....I only write melodies to others lyrics IF they accept what I come up with WHICH is usually pretty good....

I can see somebody coming up with a verse melody and another person with the chorus.....That's seems reasonable. All these conversations about songwriting especially in Nashville are a red herring. The reason that nobody can break through the barrier is because they have all the songwriters they could ever use NOW....Pop Music is just as bad. I watched the Bill Board awards and none of the songs by most had a melodic ring to them and had un hummable choruses....SO It's a Completely Closed Shop for outside people to write songs....ALSO there are millions of us out here writing great songs but only a few Artists singing on the stage.....just the way it is....As I always say DON'T QUIT YOUR DAY JOBS...which BTW is a Great Title....