I dunno know if Mich CT changed their tread pattern,
but that is not unheard of and quite common. Tread pattersns are normally proprietary and most have design patents to protect their design. Fro example BFG AT are so distinctive no other tire can be mistaken for them. However, even BFG A/T underwent subtle but significant tweaking in 2000 when they replaced the old BFG pattern with the KO pattern. The tread blocks were adjusted in their size and spacing, the center blocks got closer together, more siping in hte blocks, and a higher shoulder. Badyear's POS "RT/S" went through at least 3 tread designs in 5 years. That implies they could not get the tread pattern right. So it would not surprise me if Michelin CT did tweak the tread design a bit. Remember that they get feedback from customer usage in all types of weather, seasons, and abuse, and input that into the next level of tire design.
As far as feeling any difference, have you driven in the snow and rain yet? Even Dunflops will do alright in dry summer weather. It's the rain and snow that they go to hell. Have you driven the Dunflops in rain and snow to get a base experience to compare?
