I suppose I should clarify the shades of the meanings I'm using for those three terms, since much of the problem is that they overlap considerably. Indeed, "deluded" and "deceived" are considered synonyms, except in connotation, and both are the result, in a sense, of dishonesty.
- Deluded: Believing incorrectly with a sense of confusion about it.
- Deceived: Misled, operatively by others.
- Dishonest: Intentionally lying to others, especially, and to oneself.
So, in my use, delusion operates primarily behind one's own cognitive biases, being deceived is a state of being misled by others intentionally or unintentionally, and dishonesty is meant in the strict sense where someone is intentionally saying something he or she knows or strongly suspects not to be true. Part of the point of the whole thing is not to split hairs about where lying to oneself lands in the triangle, etc. They're in here.
I thought of calling it the "Believer's Triangle" having in mind a mental image of the Bermuda Triangle, into which there are associated mysterious phenomena, like believing that the Holy Trinity is more true because it doesn't make any sense at all.
Incidentally, I could probably have called it the "Believer's Uncertainty Principle," in homage to Heisenberg instead--"we cannot determine the accurate state of a believer's degree of being deluded, deceived, and dishonest in any of his or her apologetic-style arguments or thinking." The general point is the same: language isn't doing us a great job here at being able to nail down exactly which is which with them, and we don't possess the kind of knowledge in most cases to tell the difference, even if we often can smell a bullshit artist at work.