I haven't posted in a long time and I can't believe I am allowing myself to be sucked in, but here goes... I believe the original policy was arrived at by revelation and that the current policy is also the product of revelation. There is no contradiction. First of all, contrary to what many are saying, the policy was not rescinded or put back to what it was before. The newer version still does not allow children of gay parents who are cohabitating to be blessed or baptized unless certain requirements are met. The new version simply better explains the requirements for the exception and moves the responsibility, for the exception to be made, to the bishop instead of the First Presidency.
I believe the original policy was exactly what the brethren said it was, the result of a sincere concern of causing a divide in families with gay parents. It was a concern born out of love, and nothing else. The brethren discussed the matter and sought to know the Lord's will. Through the revelatory process, it was determined the will of the Lord was that children in such families should not be blessed or baptized, unless the parents fully understand and support that the child will be taught doctrine, concerning chastity and marriage, that is contrary to what they are seeing at home. In addition the Parents understand that ministering brothers or sisters will be assigned and they will be contacted from time to time. In the case of a blessing, the parents must understand that when the child nears the age of eight, preparations will be made for the child to be baptized. If these conditions are met, an exception can be granted. The First Presidency learned, over time, that every time an exception was sought, it was granted. The revised policy simply shifts the decision to the bishop, but the requirements must still be met in order for an exception to be made.
I will admit, from my perspective, that the written policy was badly worded and didn't really explain the process of granting exceptions. However, the written policy was not intended for the public and , although not spelled out in the handbook, Stake Presidents were instructed on the process for granting exceptions
Ultimately, the only real changes are the wording and who makes the decision for an exception. Otherwise the policy remains the same. Both were arrived at by revelation.