*taking it back to the original topic, nudging others to the "new thread" button*
I agree that there is an advantage to being depressed. In addition to what the article already said, I found it interesting in history classes that periods of sociopolitical tumult breeds geniuses, lending meaning the saying that "necessity is the mother of invention." Or, "when the going gets tough, the tough get going." This brings me to something that I think may also be true about depression, evolutionarily speaking.
In another
thread about pain I agreed with the notion that pain, particularly chronic pain, helps to weed out unfit individuals. Pain itself not being necessarily advantageous, but to the species as a whole.
I think the same notion can be applied here. Those who can deal with depression are better fit than those who cannot. There are two reasons I can think of why this is true:
1) Individuals who are especially vulnerable to depression, whether they suffer from severe bouts or chronically, may also be poor at making decisions or suffer from hormonal and neurological imbalances. Counselors target the former, psychiatrists target the latter. However, evolutionarily speaking, this may not be ideal for the group if the depression is genetically dependent.
2) Individuals who aren't genetically prone to severe or chronic depression but become so anyway may be in an environment they aren't well suited for. As a farmer may be unsuited for being a pop musician, or even an elephant unsuited for flight, some individuals may not be suited for the environment they are in. If they are fit, they will survive, and perhaps either adapt or move to a less threatening environment.
I don't mean to imply that those who are chronically or severely depressed are unfit for survival, but I think that this notion does add to the role of depression in the evolutionary process. While some depression is normal and indeed advantageous for some situations, it also helps to select more fit generations for the constantly changing demands of the future.
As for doctors' premature prescriptions: If not done so already, I think prescription protocols definitely ought to be reexamined by a board primarily concerned with human well-being than with healthcare finances. However, this may be impossible in the U.S. ... unless there is reform. BUT THAT'S ANOTHER THREAD.