Your statement assumes that Adam and Eve’s disobedience was really just based upon a healthy desire for knowledge, knowledge that could not have been acquired any other way. I would disagree with your statement that the desire isn’t sinful. It is exactly the desire that is sinful; the desire to be equal with God rather than to be faithful to God and trust in Him. It assumes that Adam and Eve were walking around in a cloud of ignorant bliss, rather than being created perfectly in God’s image and likeness. I have made this argument more than a few times (just ask Parker) and have never really understood the LDS viewpoint.
In short, Adam and Eve already knew goodness. How could they not? They walked with God in the cool of the day and wanted for nothing. The only thing they didn’t know was evil, in that they had not experienced evil. So, the only thing Adam and Eve could gain by eating of the fuit was the knowledge of evil. What did they get back for their disobedience? Suffering, weakness, toil, pain, and finally death. The serpent lied to them. They did not become “like God”. They became less like God. What they desired was not something good. They had been convinced, through the lie of the serpent, that God was holding out on them. Why could they not eat of this tree? They could eat of any of the other trees. They lost trust as doubt was placed in their hearts. They wanted to be like God, but without God. They were, in fact, already like God as they had been made in His image and likeness.
I just realized that this is getting off-topic. I’ll try to find the other thread in which this was discussed in detail as it is an extremely important subject in understanding the purpose of our salvation and the state of the human condition.