There is conditional healing, and unconditional healing.
The ego's healing is conditional healing. It says that all problems are different, and so diagnosis is needed to analyze and properly identify the cause - from many possible causes - and that doing so will inform us what needs to be done to produce healing.
The trouble with this is that it makes sickness real, making it irreversible, then comes up with an explanation for it which does nothing more than justify why it is real, making it even more irreversible, and then is practically powerless to cure it. The ego then only has special magical solutions which mostly do not work, and which definitely do not cure. The ego does not REALLY want you to heal, and its efforts to both diagnose and "treat" sickness are actually efforts to MAKE YOU SICK. This kind of healing is not really a healing solution AT ALL!
God's healing is unconditional. God does not need to figure out which of many causes has produced a problem. He knows that trying to do this would make the problem real. He also knows that there cannot BE multiple causes, because He is the ONLY cause of what is real. He also knows that finding one of multiple answers, and prescribing one of many possible remedies, would only partially assist in its removal.
He instead holds firm in the knowledge that healing is permanent because healing is truth. He simply further expresses and extends His Power to demonstrate that it is true, through the miracle. He simply CURES the problem, showing that it is not a problem at all. He does not wait on diagnosis, He does not adjust his response based on the hierarchy of problems or the apparent difficulty. One problem, on solution. BAM! Gone.