S/K didn't skate well at Nats last year, they had an error on the rotational lift when he halted the rotation before the dismount in both dances so got level 2 both times, she didn't get into position holding the blade fast enough on the twizzle in the SD, so level 2 again, they couldn't get the key points in the paso pattern (not even getting the worlds minimum at Nats when the GOE is crazy generous...) and in the FD one of their step sequences was so poorly executed and the turns were so weak that it only got a level one. Even with the technical mess, their PCS in the FD was held up to be the 2nd highest overall. I/Z had one level 2 lift in the FD, and that was the only error across the whole competition. Completely different to happened to I/Z did this year.
And again even with the mistakes (although this season it's been Ruslan's fall at CoR, which was no worse than Nikita in the FD here, Bukin in their Russian Cup event this year, Stepanova at Worlds 2014, Nikita in the FD at NHK 2014, Nikita at Worlds 2014, Nikita at Euros 2014, Nikita at Nats 2013, Nikita at Worlds 2013, Nikita at Worlds 2011 so really why are we talking about I/Z being the disaster prone team when all the Russians make mistakes? and then Lena's freak trip in the SD which can happen to anyone, like it did to H/D at GPF this year & C/B last year, are they also considered sloppy messes of teams?), the international judges rewarded them more than they did a clean S/B.
Clean S/B v clean I/Z has never ever come out with S/B on top in PCS from any panel of judges except the ones this week.