Dualwielding different speed weapons, why is the slower weapon graphically forced in to the main hand?

Question

I noticed that when wielding a fast fist-weapon in the mainhand slot, and a slower mace in the offhand slot, the game will graphically swap the mace to be displayed in my monks right hand. Is this the effect of some mechanic so that the skills will hit harder since the damage-range of the slower weapon is higher, or what's the idea behind this?

It's easy to reproduce, just equip a fast weapon in your mainhand, then put a slow weapon to your offhand, and you will see the slower offhand weapon actually appear in the mainhand and the faster mainhand getting switched to offhand.

Oh and I'm not talking about the item screen ragdoll, it happens in the actual ingame model of the character.

Answer 1

This is not reproducible for me. It must be a graphical error, as there is no mechanic that I know of that would be affected by the hand in which you hold the weapon.

Edit: The order of your weapons does seem to matter for some skills, but the effect remains unreproducible for me.