There's always a mathematical superior option. There will always be a feat that gives you more DPR, or AC, or Accuracy than the rest.
If all you care about is damage. One feat will always be on top. That is a fact.
But when "on top" can mean "half a percent extra damage dealt, some of the time" or "one percent less average damage taken, most of the time," the variance of the dice and the unpredictable idiosyncrasy of individual tables become overwhelmingly superior factors. It's difficult for those factors to overcome the feats as presented. Not impossible, to be sure, but difficult. Modify or remove them, and suddenly--even if there still were a single highest peak--the height difference is small enough to make a collection of strategies more-or-less equally valid.
A curve can have a single highest peak, without the height difference being
meaningful to the end-user. Two TVs could be precisely equal in price, and one could (frex) have one of its statistics slightly ahead of the other--but if the end-user cannot detect the difference, then it might as well be no difference at all, at which point chance or personal preference are the only meaningful determiners of what to choose. Perhaps the end-user already has a DVD player of the same brand as one of the TVs, and thus goes with that because, ideally, it will be easy to get them to talk to each other. (Personal experience has led me to question this, of course.) Or maybe one is made in China and the other is made in the United States, or a friend bought one of them previously and found it easy to use. None of these metrics has any bearing on the effectiveness of the device
as a TV, but all of them can factor into the choice when the differences between the two are reduced far enough.
What exactly counts as "reduced far enough"? Not really an answerable question, I'm afraid--it's essentially the sorites paradox (when does a heap stop being a heap?). It would seem that a lot of people--what fraction of the playerbase, I have no idea--agree that GWF and SS, as they currently exist, are too much more effective than the general average of other "good feats."
It also helps, I'd say, that most people tend to list 3-4 different feats that would all work for *both* a ranged and a melee character, and which are useful for reasons other than simply jacking up damage, whereas GWF and SS are both much more specific than that and solely about the damage.