Every single Goodyear Eagle that I've owned has split all the way around through the tread band long before the tyre tread depth wears out. I've even posted the photos on here. It's the very reason that I went back to Michelin. It happened on both Assy 2 and 3. I was happy with the Michelin PS 4S on the Omega so I swapped out the factory fit Bridgestone Pretenders on the Audi's 20" wheels and it transformed it.
Yep....exactly my tyre, and exactly what they failed on.
I also had a set of these Goodyears on my Omega which did exactly the same - splitting in the tread grooves way before the tread itself was down. I also had a set of Dunlops on the same car, and they also did the same, which, according to a tyre fitter I know, is also a common failing of Dunlops too. I have stuck with Michelins ever since. The last set of PS4's I bought for the Omega (235 45 17 97Y's) last year were £422 fitted at ATS, which was a similar and in some cases a cheaper figure than other possibly less 'regarded' makes.
ATS are 'agents' for Michelin so it is worth checking when they have special Michelin discounts on, which in my case saved me approximately £120 compared with quotes for the same tyre at other places.