OK, happy to elaborate:
For me, if we're talking frontside and the pows been scrapped mostly down to ice and crud, a "narrow" (in today's terms) carver's called for: RX8, Supershape, Mach 3, Allstar etc. By contrast, a mid-fat is a crossover design that allows you also to hit the backside and some fresher stuff.
And let's face it, unless we're racers, powder is prized more than ice. We ski hardpack groomers only if there's nothing softer and deeper around. So since any crossover involves compromises, it makes more sense to me to aim for a ski that excels in powder and chop, but can carve hardpack if needed, than the other way around.
IMO, the AC4 is the other way around. When I demoed the 170 and 177 at Vail, I felt like I was on citizen racers. Absolutely slayed the scrapped off frontside. (So no, Troutman, I'm not saying that edge grip is bad. I live in the NE. We know and love edge control.)
But it snowed hard all day at Vail, and neither length really liked the back bowls by lunch. The 170 was hooky and the tips dove. The 177 smashed, rather than floated. It was ponderous and heavy compared to a lot of other mid-fat's I've skied. I attribute this to the stiff, damp fronts of Volkls using Marker Pistons. You can't have it both ways, Volkl people: If your tip is optimized to hug ice at speed, and take away those nasty vibrations, it won't float up in powder at modest speeds.
There are plenty of wider mid-fats that aim for the backside but still carve decently to wonderfully - the iM 82-88, the new Fury's, the Stockli XL, the Karma, the Snoop Daddy, the B3, the 666 and 777, the Scott Aztec, the 8000 and 8800, the AMC 79, for starters. So it's not impossible.
Jer, I'm not saying that Volkl hasn't made a lot of solid evolutionary changes in it's ski body design. But think about how long it's mined the basics: Sensorwood core and one or two sheets of metal go back at least to the early 90's, and the raised upper edges came with the first Superstar p50. Those other bits you listed showed up in other skis well before Volkls. I'm not the only observer who's commented on how Volkl has put most of its energy into integrated bindings, and I'm not the first who's noted that those bindings have become more and more of the ski. In fact, that's Volkl's true innovation since the 90's - system bindings that let the ski flex. So they deserve serious kudos for that.
But I started skiing Volkls in the 90's because they felt unlike any other ski made: glassy and lively at the same time, responsive in any condition. Now they're just smooth and beefy, like a lot of other good skis. The bindings have run away with the ski...