I have not been following the thread, so if I have missed something, do not hesitate to point it out to me. That said, I was asked about the matter and here is essentially my response:
I think the issues PPS and Nang are raising are important, but I am not so sure Tambora was implying what Nang and PPS are denouncing in the first place. Depending upon the venue, persons in ordinary conversation may say the Persons of the Godhead work together as long as we are not assuming the Persons of the Godhead are capable of not working together, which is implied, albeit unstated, if one is saying the Persons of the Godhead are cooperating with one another. So it is all about the context wherein discussion is taking place, e.g., in the line at a grocery store, at a family discussion at dinner, in an academic forum, etc.
For the record from the teachings of Scripture, there is but one will in God, not three wills, with each of these three wills within the subsistences of Godhead being independent of the other's will.
Shedd defines the human will as: “that voluntary power of human nature which determines the continuous movement of the soul toward its ultimate reason for living, according to those principles of life which together make up human nature” [Shedd, Essays, 233–234].
I think we can adapt Shedd by defining God's will as: “that voluntary power of the divine nature which determines its eternal movement as the ultimate reason for being, according to those perfect principles of existence (God's attributes) which together make up the divine nature”. (This is a work in progress, so be kind.)
When we speak of "will" we must understand that the will is attached to (belongs to) the divine nature. Natures have wills, not persons. This applies whether speaking of God or human beings. Belonging to the person as a property is the "I", "Thou", "He", that is, the sense of self. So when the Son says, "I do the will of my Father" it is the Person, the "I", that does/acts. Try to keep in the mind this useful memory aid: Natures are, Persons do/act.
Connected to the will is the notion of volition. Volition is the expressive faculty used by the will to carry out its choices through actions in thoughts and deeds. The will chooses the principles determining the how and why of action, volition carries out those choices through individual actions.
Again, will belongs to the divine nature, but there is an "I," "Thou," and "He," owing to the personal properties. Accordingly, The Second Person of the Godhead knows Himself as the Son of the Father, and rejoices in it. Without this personal knowledge He could not have volunteered to make Himself of no reputation. Similarly, Our Lord states in His prayer in Gethsemane, "not my will, but yours be done". From the above, we should know that this is Our Lord's speech in His humanity, for His divine will is not out of alignment with the one divine will that all Persons of the Godhead partake within equally wholly.
In summary, unless Tambora has been implying in her posts (as stated, I have not been following the thread) that there are different wills in the Godhead, which would be falling into tri-theism, speaking of cooperation among the Persons of the Godhead is an acceptable form of speech, given my caveats above, that can be further dissected for more clarity in normal conversation.
Yes, we should all be good theologians, but some of us are not a adept with the language of theology and thusly should be less quick to take another to task when the less informed make infelicitous statements in theological discussions. Unfortunately, some are very scrupulous when it comes to how things are said no matter what the context of the things being said. So when I interact with these folks I take careful pains to construct what I have to say understanding that they will examine each and every word. These persons will not change, and I respect that, adopting my discussion style accordingly. Conducting an edifying discussion requires both parties to attempy to understand the other's methods and modes and try to work within that framework. All too often we are all occasionally guilty of hair-trigger "ready, fire, aim" responses when it comes to matters of the faith
The average person encountering the painfully scrupulous will be taken aback when they stridently point out his or her's less than perfect theological speech. I think there is a time and place for attention to detail, but not in ordinary discourse, especially in a generally anti-Reformed/Calvinistic environment like TOL, where care should be taken to not immediately give offense without warrant. In this topic at hand, had I been active, I would have sought clarification as to another's view about their notions of the will of God first, "One will in the Godhead?" "Three wills?" and proceeded accordingly.
The question I was aksed is exactly why we need theologians. From theologians we are not told what to say, but how to say it in order to avoid falling into error.
If the reader is inclined to dig deeper, I recommend the following as a very thorough (and academically dense) treatment of the entire topic of the will of God: http://www.puritanshop.com/shop/the-two-wills-of-god/
AMR
The direct assertion by Tambora was that such working together by Father, Son, and Holy Spirit was Synergy; and it was originally when confronted about having admitted a Monergistic Soteriology position without realizing it. She then retreated from Soteriology to Theology Proper as a typical Arminian smokescreen to insist Synergy was relative to Father, Son, and Holy Spirit.
She was corrected many times that sun- and ergon could not pertain to Father, Son, and Holy Spirit in the manner she insisted, since synergy is contingency and God is Non-Contingent according to His incommunicable attribute of Necessity. This cascades to impugning His Simplicity, for He is not comprised of constituent parts that have such interfunctionality according to merely sun-.
This must all be according to perichoresis, not synergy. She refuses to relinquish usage of the term because she employed the base-word fallacy of looking merely at a simplified meaning of synergy.
This is no small issue; and has gone far beyond ignorance to willful stubborn usurpation of historical doctrine, etc.
This makes Father, Son, and Holy Spirit into individual beings. It's at least functional and conceptual Tritheism. And this is one of the huge reasons I have opposed modern professing Trinitarians, since they're not actually Classical Trinitarians by passive ignorance at the very least.