Pax said:I prefer to make each one a simple "becomes 1 wider" effect, and then let them stack. Thus, rapier or greatsword, neither benefits more from being keen than the other does, in terms of % chance to threaten.
Ridley's Cohort said:All the special bonus you need are Str and Power Attack. With a more potent (albeit shorter duration) Bull's Strength and Power Attack in 3.5, the falchion critmonster would get a huge boost if you allow keen to stack with improved critical.
The falchion critmonster was very powerful in 3.0. It is a Good Thing to remove the stacking, especially given the changes in Bull's Strength and Power Attack.
Elder-Basilisk said:They reduce the effectiveness of other types of fighters too. However, the reduction disproportionately effects offensively focussed fighters like the falchion critmonster. Finesse fighters are less likely to rely on strength and sword+board fighters tend towards a defensive focus that makes round one damage less important (duration) and that often means that their role in the party is something other than primary damage dealer.