I don't know. The advantage of such expert systems is that they have access to the entire database, never forget anything and can recalculate all relevant proba

I don't know. The advantage of such expert systems is that they have access to the entire database, never forget anything and can recalculate all relevant probabilities on the fly. Your doctor can't do that. Although the linked site failed completely (as far as I can tell, because its buggy!), the WebMD that was linked elsewhere correctly diagnosed my condition in less than 2 minutes. It took a real MD 2 hours+ and that included an (unnecessary) X-ray. I don't think it's comparable to remote diagnosis being hard - that is very dependent on how doctors recall information, and visual information or feedback may be very important to them. An expert system has no such limitations.