As far as I knew, the biggest difference between MPD and DID is the name - I thought that DID was the name-changed, updated-with-new-knowledge version of MPD.
If I am understanding what the article writer is saying, then I disagree with a lot of what he's written. From my own experience, his definitions aren't quite correct. Our first split happened at 3 years old, yet we have an ISH. He goes into further detail about MPD later on, saying that to have it, a person must have had life-threatening trauma before age 7, had to be highly hypnotisable, had one "good" and one abusive parent, and been the only of all the siblings to be abused. He seems to say that you simply can not have DID if it starts before you are 7.
Again, from my own experience, these things don't make sense. I/we did split before age 7 - that's for sure. Both my parents were equally loving, and equally good at making honest mistakes. They cared for me and my siblings equally. My siblings (particularly sister) were all abused, as I was, and by the same person.
Then there's what he says an ISH is (in spoilers to take up less space):
[spoiler]
Characteristics of the Inner Self Helper (ISH)
A. Prime Directive of the ISH is to keep patient alive until her Life Plan is completed and fulfilled. The ISH will prevent suicide in any way possible.
B. Has no date of origin; has always been present.
C. Can only agape love; is incapable of hatred.
D. Has awareness of and belief in "The Creator."
E. Is aware that the Celestial Intelligent Energy (CIE) put her in charge of teaching this person how to live and move forward properly.
F. Is able to work on the inside of the patient's mind, as co-therapist, while the human therapist works on the outside.
G. Knows all about history of patient and can predict short term future.
H. Possesses no personal sense of gender identity, but will assume either gender the therapist is comfortable with.
I. Talks intellectually instead of emotionally, carefully chooses precise words, speaks in short concise sentences; prefers to answer questions; gives enigmatic instructions. ("Teach her humility today.")
J. Avoids using slang; does not have the capacity for put-downs or guilt-trips.
K. Is aware of patient's past lifetimes.
[/spoiler]
Many ISH's that I know or know of have a great deal of knowledge about the whole system and the life the "person" has had. Many also speak intellectually and are careful about what words and sentences they say. According to the author, ISHs are angels, placed by G*d/"The Creator" in the person to help them get through life. Now, while I wouldn't dare say that no ISH is an angel, mine is not, and none of my multiple friends have mentioned having an ISH that is an angel. Also, how does this work for a system where the ISH is atheist? Many ISH's that I know do have a preferred gender, and it's not whatever the T prefers them to be. I don't know how it is for others, but my ISH can hate, can put people down and guilt-trip people, but chooses not to. Myself and my ISH both believe in an afterlife, but not reincarnation - so how would K apply to us, and others with the same/similar belief?