The onlything the BKGS doesnt toss in the air are the very large enemies, they just get knocked over or stunned. Its a fixed animation like they sai Zyrax, also i wish they would un nerf Iron Flesh it would be so much more useful in its old "invincible" form. Just make it so that lightning based damage goes through to balance it out seeing as your made of Metal right! Would also make Sunlight Spear super awesome against Iron Flesh as they wouldnt be able to DODGE IT lol.
I never got blasted by lightning damage to test it, but I remember hearing that your lightning defense is indeed cut by Iron Flesh. I suppose the Titanite Demon near Andrei would be more than happy to assist in testing that out.
"I'd rather betray the world than let the world betray me." -Cao Cao