It's PTR, you have to realize that most ppl will want to try the new item. And from the look at the site, WD is not the top class, both crusader and monk are above them. Even after logging into PTR looking what you're saying about 10gr above is so not true.
Current standing on PTR:
#1 Crusader GR101 (LoN bombardment)
#2 Monk GR100 (Rainment Gen)
#3 Witch Doctor GR98 (LoN Spirit Barrage)
#4 Wizard GR97 (Firebird Archon)
#5 Demon Hunter GR95 (LoN Fok)
#6 Barbarian GR92 (LoN Thorn)
So there is no class with 10gr difference, the difference between barb and crusader (not wd) is 9gr. And this might be different once it goes live, there is far from the same amount of ppl playing and pushing on PTR then on live.