Since it seems like developers do not see a point in looking into the probable Malfunction of the Massive Critical property, maybe we can come up with alternative stats for the weapon, and get rid of the Massive Critical property entirely. The reasons I suggest that are:
1. The Cavalry saber doesn't offer anything beyond its extra slashing damage property.
2. Its damage peaks at a 1d6+1d4+STR-1, which is at an average of 4+STR Damage.
3. If you compare that to a mundane longsword, at 1d8+STR, its average is also 4+STR.
4. The difference is that the longsword doesn't come with Skill Penalties which include a -1 Parry AC (Both discipline and parry are high priority skills for combatants).
5. Spells that increase Weapon Enchantment (Magic Weapon, Greater Magic Weapon, etc) do not overwrite the -1 EB on the Cavalry Saber, making such a spell or varnish necessary to simply negate the penalty (-1 AB, -1 DMG).
I haven't seen other rapiers in the loot table so my suggestion isn't as informed as it could be but I suggest the following stats to replace the original ones:
- Extra Melee Damage: Slashing
- Damage Bonus: Slashing 1d4
- Minus 1 Dodge AC
If you want to get technical, the cavalry sabre is also used as a dueling weapon, and giving a penalty to parry doesn't seem fitting.
On the other hand, the elaborate guard which allows the wielder to extend the arm with more hand protection than a simple crossguard also comes with the risk of making the arm a target due to overextension.
Other suggestions are welcome!