@boagie,
Hey Boagie,
I can see that view from your perspective crystal clear. I am speaking as someone who is actively engaged in the spiritual encounter that is being described. I have to say I have seen some very distinct differences between spiritual influences over people that are results of the type of spirit they are exposing themselves to.
I guess I am switching now from philosophy to eye witness accounts, but here we go.
For instance, I have encountered people who have had experience with people with certain powers--this one was a strange kind of gift to see the dark secrets of a person's heart and tell it back to them. After the experience wtih this person, these people have had many terrible tragedies in their lives. When we prayed a prayer with them renouncing that spirit and inviting the Holy Spirit we were able to see an instant change in them. There have been other personal experiences like this and many other second hand ones.
My only point being there are spirits that invite terrible things into the lives of people, and only one Spirit I know that has set them free. My experience is limited to that Spirit, so you may know of others. But I can only guarantee the path that I have walked.
The question isn't which religion is the 'right' religion. The question is which Spirit brings freedom the the life of the follower, and which destruction.
That being said, the people I describe were Christians. We are not immune, we just have the Power to overcome the spirits that cause destruction by the One we receive by surrender to Christ.