Bashing since size change

[Zukal]

I'm doing some exp with my Barb warrior and I've noticed he misses bashes absolutely way too often. Before size changes with 99 bash a bash miss was extremely rare, I could even 2h bash reliably, but for the last 2 hours I've been doing exp in SM and i've missed at least 25 bashes resulting in my group eating 5 cyclones and 3 earthquakes. Something is wrong here.

EDIT: Swapped shields for a little heavier one, bashing improved, but with 99 skill I don't think the weight of my shield should be such a determinant factor.