[quote=@GreivousKhan]
<Snipped quote by MelonHead>

The simple difference is you can break someones bones from the force of a sword blow much easier with the coat. It's the equivalent of wearing a breastplate, if covers and protects the chest, or in this case, the back, not sure how it equals up to a full suit of armor, but OK.    
[/quote]

I'd argue it's actually better, it's lighter, covers all the vital areas fine, and has none of the weak spots at the joints that conventional armour has.