pro's and con's either way I suppose.
On the pro side it would be nice to have an organization which can represent detailers and increase professionalism/awareness to the public, similar to ASE when it comes to mechanics.
On the con side, you become limited by the IDA's ideals. I have had a run in with several of these associations because I simply don't agree with how they promote detailing nor do I understand the qualifications where setting forth.
Realistically, having a major organization to represent detailers would be a benefit (I think) to many detailers, but several have tried, and none have really come close to succeeding.