I guess what makes me scratch my head in all of these threads is what the reason for defining the term is. If you are trying to decide whether you are suitable for a given site that is labeled "Advanced", it seems to me that you need to know why it has that label. In general, I think sites get that tag if there are conditions or topography that can be conducive to problems -- for example, a site with a hard bottom at 600 feet, or a site known for strong or unpredictable (or up and down) currents, or a site where navigation is very difficult, or where surface conditions can make reboarding the boat very challenging. I think the term, rather than identifying really "advanced" divers, is simply a red flag to discourage beginners.
I was in a situation similar to the one posited in the original post, just a couple of weeks ago. A site which is normally benign, and by the tide forecasts should have been, turned unfriendly underwater due to an unexpected, strong current in precisely the wrong direction, and on the surface, proved unfriendly due to rough water conditions that had developed during the dive. All three of us handled it calmly and appropriately, but I remember thinking, "Man, am I glad we didn't have any new divers with us!" I would not say the ability to handle that day's dive made us "advanced", but it certainly made us something beyond beginners. Thal's "competent" covers it neatly, and I suspect most Puget Sound divers of any seniority at all have gotten there.
I was in a situation similar to the one posited in the original post, just a couple of weeks ago. A site which is normally benign, and by the tide forecasts should have been, turned unfriendly underwater due to an unexpected, strong current in precisely the wrong direction, and on the surface, proved unfriendly due to rough water conditions that had developed during the dive. All three of us handled it calmly and appropriately, but I remember thinking, "Man, am I glad we didn't have any new divers with us!" I would not say the ability to handle that day's dive made us "advanced", but it certainly made us something beyond beginners. Thal's "competent" covers it neatly, and I suspect most Puget Sound divers of any seniority at all have gotten there.