I had an entire post written up about how wrong you where. Basically came down to you having the higher AC, but the barb having massive hit point bonuses and a better attack bonus despite the -8 from dual-wielding, but finally realized the whole thing was pointless to compare unless we had actual stats for the two characters. The balance shifted a little more when I realized that the barb could forgo the fortification since he's already immune to your sneak attacks and the increased AC would be of more use that not having to worry about Crits on a weapon that wouldn't deal as much damage on a crit as the barbs would on a regular hit.