I have a bit of a different take on this. The practice of medicine and the verbalization of what was wrong came first. At some point that verbalization began to be written down. So we then had the practice of medicine plus the writing down of the diagnosis. All of this existed way long before computers were invented.
The ICD and CPT codes are an attempt to turn into computer language what the doctors have been writing down for centuries. It is the written diagnosis / procedure that is the legal definition of what is wrong with the patient and how it was addressed - not the ICD and CPT codes.
So - a doctor may be extremely proficient at making diagnoses (plural), and less proficient in selecting the codes that best match his diagnoses (plural). That is, after all, what ICD10 is supposed to address. The ICD9 codes are much less specific; the ICD10 codes, of which there are thousands more, are much more specific.
So - if the doctor's written notes support a 362.11, but the doctor wrote down 362.10, is it illegal to change the code?
If an insurance phone person says "we can pay this if you can change it to 362.11", I would like to think they are saying "have the doctor check his notes to see if they will support a 362.11". To me, that is an approach far removed from simply advising someone to change a code just to get it paid.
As we approach the change-over to ICD-10 (assuming it ever happens), I imagine it is going to be a nightmare of incorrect coding submitted to the carriers. I would not be surprised if they are training their staff in the art of educating their clients (the doctor's and their staff who submit billing to them) on which codes are more useful, and which codes are less useful - assuming the written documentation supports the more useful codes.