First of all, let's set this straight. You should not imagine my views are in any ways reflecting that you need to change a thing. This is a history lesson and some Qabala, not me saying it will not work if you do it the way NAP says to. Geof Gray-Cobb did not know Hebrew, nor did he study direct Hebrew Sources, from what I have found out. But he was HEAVILY influenced by people who knew a good bit more, and worked with some. Some were ashkenazic and some were just mangled hebrew. Thus I can easily rationalize his pronunciations and mine are WAY different. In some cases, it is obvious, in some I have to question how much of what I know he might know.
What is Dee-Hay-Thooth to you? What if I I told you to me, based on his sigil, his words, his method and his use he reveals his source and his mistake in pronouncing it.
The word should be pronounced "de-hee-tee-ath" (Daleth Heh Ayin Teth Yod Tau) it means "You God, Have Covered". It is from the Psalm 89, and it means "thou God concealed." This is the Messianic "Psalm", that says the Messiah will be of the blood of David, as some of you may know. Furthermore here is the breakdown that tells me where his root is.
This Psalm is used to beg forgiveness for sins, known and unknown, that one may be "yasha" - i.e. delivered from evil. This is the psalm of Uriel. The Messiah is the bodily manifestation of the spirit of this Psalm. This psalm was written by Ethan, who was master of the brass symbols in David's band of musicians. He was known as the wisest man until Solomon. He is said to have been the man who created the name AGLA, as notarikon from the Gevurot, the second prayer of the Amidah. Part of this is because His own name means "Endure until the End" - a funny note for those who know a certain Frater Perdurabo.
So needless to say with AGLA, Uriel, and the grounding effect of it, we can easily see this as a way of doing the same thing as an invoking "Earth" Pentagram (overlaying an invoking Pentagram of Spirit Passive) in the Northern Station of Water, the place of greatest symbolic Darkness.
Thus AGLA is the God of Ethan. He was instrumental to the temple in the time of David and in the time of Solomon, but he retired it is said, to his own solitude as he began to disprove of Solomon's interactions with the goeh, or gentiles (Gimel Vau Yod - Heh). This is the word Go-we-yeh, which means "impurities of nations", which KJV translates to "filthiness of the heathens". Solomon integrated these cultural practices in his many wives, and their Gods. Ethan was a figurehead of the messianic movement. It is a Maschil, not a Mizmowr. This means it has a element of deeper meaning and should serve as instruction. The use of this word as a chant or amulet is accompanied with the prayer of Azariah, son of Ethan, which was removed from the Protestant Bible.
This word is used in relation to the removal of sin and the deliverance of evil, which is supposed to lessen guilt, shame, and fear which can prevent success.
Now for the integration of the sigil. I have seen several views of this, but this is mine, and I can only tell you it will make sense if you do it. It seems, to me, to be attributed to Uriel, Archangel of Salvation.
Here is a simple set of directions far different than his, made easier:
Extend your right arm upward at approximately a 45 degree, keeping the elbow straight. Then rotate the pointing hand down even to shoulder level keeping the elbow straight, then move your pointing hand across STRAIGHT to your left shoulder, all the while keeping the elbow straight. Then, keeping the elbow straight, move your pointing finger diagonally back to the original position. This makes a Right Triangle, a sign of Light and Fire, and a proto-biblical vau in the center.
In the approximate center of the triangle, which is about a foot above your head, draw a semicircle from the left to the right, and then bring the pointing finger straight across to the midpoint between the two ends of the semi-circle.
Then draw the hand down to the waist level and draw a small circle counter-clockwise.
The more accurate pronunciation would be applied thus: (though it is not authentic to draw it in the air this way)
Put hand up
Dee (Down)
Hee (left)
Tee (right diagonal to finish the right triangle)
Ahh (semicircle and "stem" to waist")
Th (small counter-clockwise circle - which is in Western Magic to "close the symbol")
A vau in a triangle is STILL used as a magic sign of mainly because vau is 6, extended is 12, which is the key to the right Triangle. I believe this is why he is extending the OO sound so much in the drawing of the sigil. This sign of the nail (Vau) in the 12 of the right triangle, is the sign of the Messiah as the gathering of the Mezel Ha-Mazloth, i.e. "Zodiac" - and one of the reasons 12 tribes, 12 disciples, etc. The Vau (Nail) is 6, and the Triangle is the proto-Daleth, which is Door. The nail holds the door (i.e. tent flap). Daleth Vau is 446 extended (Aleph and the value of the 12 simple letters) as well as the word "destruction" . The value is 10 in simple, a number sacred to God praised by David, by his ten-strings of his kinnown. D and V are the letters of the name of David, with 2 daleths.