Scather is listed as a Bastard Sword in the protos.tab file but it does 2d6 damage compared to the 1d10 of Fragarach, and cannot be wielded in one hand even though it is a bastard sword due to it being set as "size_large". Is Scather supposed to be like that?
There can be a rule justification for that. Maybe Scather is a Heavy Weapon. Which means, the metal used to forge is err, very heavy, thus it gains in weight, and you get -4 attack bonus roll when you wield it with one hand unless you have the exotic feat : "heavy bastard sword proficiency", then finally, the damage roll gets boosted, in particular, 1d8 and 1d10 becomes 2d6. So, maybe, it's a design decision...