Hi Dana, Registering with the NDCA allows the registrant to compete at NDCA events. Competing at NDCA competitions means that you can pretty much rely on the tempo of the music and the length of time that it will be played for each heat - and it means that you can pretty rely on water being available.
But the NDCA does not "certify" teachers. Some of the member organizations of the NDCA certify teachers.
It sounds as though you're talking about a person who was registered as a "pro" by her boss. It may very well be that her boss doesn't understand what the NDCA does and does not do. Maybe the boss thinks, mistakenly, that registering his employees with the NDCA automatically means that the teachers are "certified"; or maybe the boss thinks that teachers must be registered with the NDCA in order to teach.
Or, if I want to be cyncial, maybe the boss knows exactly what the NDCA does, and maybe the boss also knows that the average student has no knowledge at all about certification. So, the boss registers the employees with the NDCA, and then uses a bit of double-talk when the boss talks to customers, hoping that customers don't know the difference between registration versus certification. The boss shows the custmomer a list of his employees' NDCA registration status, and the naive but impressed customer assumes it means certification and promptly signs up for lessons.
Or, because it's easy to find teachers who are listed with the NDCA, so maybe the boss sees paying for the registration as good value for advertising.
But if you're paying the registration fee yourself and have no intention of competing at NDCA events, then maybe you'd find it to be expensive advertising.