Have you ever needed to get a speaker approved?

Someone passed this on to me.

A group in a parish wanted to have someone from the community to speak to the parish about a particular subject. Sorry, I'm not going to be more specific.

The parish group was told that they would need to have the potential speaker approved by the diocese. The speaker would have to fill out the diocesan form for approval of his program; as well as to submit an official invitation on the parish letterhead by the parish group, to include his CV and to obtain a letter from his pastor attesting that he was a Catholic in good standing. I'm not sure what else was needed.

I understand that this diocesan approval is to make certain that speakers faithfully teach Catholic doctrine. My question is this: Why is this approval needed even for programs that are not religious in nature; but cultural or educational? And what about a speaker who is not Catholic? It seems to me that the diocese is making it needlessly difficult for parishes to recruit speakers by forcing them to jump through hoops in order to obtain the approval.

Care to respond? If I have incorrect information, please be kind enough to supply the accurate information.