I look at it this way.
If a group is consistently beating the odds, on a consistent basis, then the odds are not what they think they are. They cannot be.
The example of poker is pretty apt I think. Sure, you can play the odds in poker. You can do all sorts of things to help you win. But, what you cannot ever do, is consistently win. You can't. There's simply too much random element in poker to ever win consistently. The longer you play, the more you will lose, and that's an unavoidable fact.
So, if your group is consistently succeeding in combat, then how can it be CaW? It's not random. It can't be. Not if you are consistently succeeding. The odds are simply too great for that to be true. Even if you have an 80% success rate, you are still failing 1 encounter in 5. And I'll guarantee that no one in this thread has a failure rate even approaching that. Probably closer to about 1%
That's why I call it illusionism. It has to be. The DM is setting encounters with the idea that the encounters are not only defeat able (unless he wants the party to run away) but the presumption of everyone at the table is that the vast majority of encounters ARE winnable. You can pretend that your encounters are as difficult as you want, but, at the end of the day, most of them really aren't. They can't be. If they really were, then you'd be killing PC's more often than you do.
That's why I asked Emerikol way back how often he whacked PC's in combat. A question that got completely dodged by claiming that difficulty isn't just combat. Thing is, in D&D, failure in combat is generally a dead PC. It's pretty rare that you fail and no one dies. I'll stand by the idea that if you're playing a D&D campaign from level 1 to 20 and the PC's succeed more than 80%, then you're pretty much tailoring every encounter to the group. There's no other way it works because the odds are just too great.
The odds in most groups is likely somewhere around 95% for every single encounter. I doubt any of you see your groups fail more than 1 in 20 encounters, either combat or non-combat. 1 in 10 at the absolute outside. Whether that's due to the DM designing encounters that way at the outset, or shifting the odds during encounters by making deliberate choices (yeah, I could coup de grace the downed fighter, but, hey, we'll swing fire over to the cleric because that would be more fun...) the odds are almost never as high as people pretend they are.