To me Nashville is the finest spot in the world for songwriting. You don't have to be a country writer to appreciate that. I think Willie Nelson and the whole alternative country stuff is great, but I also think the craftsmanship in Nashville is widely under-appreciated. Many Greenwich Village poets have read less litterary novels, and are a lot less versed in litterary studies than many songwriters in Nashville.. and if you think you can play guitar.. even your average bartender in Nashville may slayer you in a guitar duel. I haven't been there, but I have met some folks that is the living proof of that. As a guitarist I'm in awe of the level the art of songwriting in Gtr town.

Songwriting is a way of communicating and co-existing with each other, so of course co-writing is essential. Both in order to learn how to write, in order to write something interesting, and in order to interact with other people about the music and the things you write about.

It doesn't mean that Nashville is the only place, but it certainly is an idiomatic place, Nashville is thE prototype of songwriting practice for alle over the western world. NSAI has a division in Denmark, and Bobby Bare participated in the Norwegian Eurovision contest a few years ago. So, Nashville is a model for how great music is crafted all over the world, and invites everybody in. So it's not really an exclusive place at all. No inside/outside, just really inspired and alert people who wants to hear the best songs from everywhere (not that everything is country).

So, co-writing is definately something to aspire to, imo. But not always a choice, for one reason or another. Co-writing is about sharing your artistic view, and as such is very much about great people skills.