New Rule
Reference
PF0000005
Text
Weapon Training (Ex):
Upon reaching level 4, a fighter can select one group of weapons, as noted below.
Whenever he attacks with a weapon from this group, he gains a +1 bonus on attack and a +2 bonus on damage rolls ((Each level of Weapon Training is a combination of the benefits of Weapon Focus and Weapon Specialization.)).
Whenever he performs a combat maneuver with a weapon from this group, he gains a +2 bonus to his CMB ((I think it’s consistent to extend the benefits of training with a weapon group to combat maneuvers performed with weapons from the group. Having the fighter become better at hitting and damaging opponents without improving his disarming and sundering abilities is strange. In 3.5 Weapon Focus and Weapon Specialization were factored in the disarm and sunder attack.)).
Whenever a combat maneuver targets specifically a weapon from this group, the DC of the combat maneuver check is increased by 2. ((A comprehensive training should also cover becoming better at resisting the maneuvers which target the weapons from the weapon group.)) The bonuses are halved to a minimum of +1 when the fighter wields an exotic weapon in which he is not proficient. ((Weapon Training is less effective in the case of exotic weapons in which the fighter is not proficient.))
At level 8 and every 3 levels thereafter (8th, 11th, 14th, 17th and 20th), the fighter either gains additional training in a previously selected weapon group or chooses a new weapon group.
If he chooses to improve his training in a previously selected weapon group, the bonus on attack rolls increases by 1 and the bonus on damage rolls increases by 2. The bonus to his CM check when performing a combat maneuver with a weapon from this group increases by 2. The DC of combat maneuvers targeting a weapon from the group increases by 2. The bonuses are halved to a minimum of +1 when the fighter wields an exotic weapon in which he is not proficient.
He also gains a +2 competence bonus to Appraise and Craft checks relating to weapons from this weapon group.
If he chooses a new weapon group, he gains the benefits described at level 4.
Bonuses granted from overlapping groups do not stack. Take the highest bonus granted for a weapon if it resides in two or more groups. Bonuses granted by Weapon Focus, Weapon Specialization, Greater Weapon Focus, and Greater Weapon Specialization do not stack with those granted by Weapon Training. Use the highest bonus for each weapon.
Weapon groups are defined as follows (GMs may add other weapons to these groups, or add entirely new groups):
Axes: battleaxe, dwarven waraxe, greataxe, handaxe, heavy pick, light pick, orc double axe, and throwing axe.
Blades, Heavy: bastard sword, falchion, greatsword, longsword, scimitar, scythe, and two-bladed sword.
Blades, Light: dagger, kama, kukri, rapier, sickle, and short sword.
Bows: composite longbow, composite shortbow, longbow, and shortbow.
Close: gauntlet, heavy shield, light shield, punching dagger, sap, spiked armor, spiked gauntlet, spiked shield, and unarmed strike.
Crossbows: hand crossbow, heavy crossbow, light crossbow, heavy repeating crossbow, and light repeating crossbow.
Double: dire flail, dwarven urgosh, gnome hooked hammer, orc double axe, and two-bladed sword.
Flails: dire flail, flail, heavy flail, morningstar, nunchaku, spiked chain, and whip.
Hammers: club, light hammer, light mace, greatclub, heavy mace, and warhammer.
Monk: kama, nunchaku, sai, shuriken, siangham, and unarmed strike.
Pole Arms: glaive, guisarme, halberd, ranseur, and quarterstaff.
Spears: javelin, lance, longspear, shortspear, spear, and trident.
Thrown: bolas, club, dart, dagger, handaxe, javelin, light hammer, net, shortspear, shuriken, sling, spear, and trident.
Example
A fighter chooses the Light blades weapon group at level 5. When wielding a rapier, he gains +1 to attack rolls, +2 to damage rolls, +2 to his CMB for the relevant combat maneuvers and +2 to the DC when defending against the relevant combat maneuvers. When wielding a kama, he gains +1 to attack rolls, +1 to damage rolls, +1 to his CMB for the relevant combat maneuvers and +1 to the DC when defending against the relevant combat maneuvers.
When he reaches level 8, he chooses to carry on training with the Light blades weapon group.
When wielding a rapier, he now has +2 to attack rolls, +4 to damage rolls, +4 to his CM check for the relevant combat maneuvers and +4 to the DC when defending against the relevant combat maneuvers. When wielding a kama, he gains +1 to attack rolls, +2 to damage rolls, +2 to his CM check for the relevant combat maneuvers and +2 to the DC when defending against the relevant combat maneuvers.
Weapon Mastery (Ex)
At 20th level, the fighter chooses one weapon group in which he has received additional training at least twice over the course of his career. ((I linked Weapon Training to Weapon Mastery. I find it odd for a fighter to train his entire career in Hammers, Flails, Light Blades and Crossbows then pick the longbow for Weapon Mastery. Weapon Mastery should be the crowning of the training and allow the fighter to become exceptionally proficient with a group of weapons which he has extensively used over the course of his career.)) He receives the normal benefits from applying Weapon Training to that group.
Additionally, any attacks made with weapons from that weapon group automatically confirm all critical threats and have their damage multiplier increased by 1 (a ×2 becomes a ×3 for example). He cannot be disarmed while wielding any weapon from this group. He can have that weapon sundered only on a natural 20 on the attacker’s combat maneuver check. When defending against combat maneuvers with a weapon from the selected group, the damage inflicted by an attack of opportunity is doubled for the purpose of calculating the DC of the combat maneuver. These additional benefits do not apply to exotic weapons with which the fighter is not proficient.
Altered rule
Source
Pathfinder RPG Alpha 3, p. 27 PZO1110AE.pdf
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Weapon Training (Ex)
Starting at 5th level, a fighter can select one group of weapons, as noted below. Whenever he attacks with a weapon from this group, he gains a +1 bonus on attack and damage rolls.
Every four levels thereafter (9th, 13th, and 17th), a fighter becomes further trained in another group of weapons. He gains a +1 bonus on attack and damage rolls when using a weapon from this group. In addition, the bonuses granted by previous weapon groups increase by +1 each. For example, when a fighter reaches 9th level, he receives a +1 bonus to attack and damage rolls with one weapon group and a +2 bonus on attack and damage rolls with the weapon group selected at 5th level. Bonuses granted from overlapping groups do not stack. Take the highest bonus granted for a weapon if it resides in two or more groups.
Weapon groups are defined as follows (GMs may add other weapons to these groups, or add entirely new groups):
Axes: battleaxe, dwarven waraxe, greataxe, handaxe, heavy pick, light pick, orc double axe, and throwing axe.
Blades, Heavy: bastard sword, falchion, greatsword, longsword, scimitar, scythe, and two-bladed sword.
Blades, Light: dagger, kama, kukri, rapier, sickle, and short sword.
Bows: composite longbow, composite shortbow, longbow, and shortbow.
Close: gauntlet, heavy shield, light shield, punching dagger, sap, spiked armor, spiked gauntlet, spiked shield, and unarmed strike.
Crossbows: hand crossbow, heavy crossbow, light crossbow, heavy repeating crossbow, and light repeating crossbow.
Double: dire flail, dwarven urgosh, gnome hooked hammer, orc double axe, and two-bladed sword.
Flails: dire flail, flail, heavy flail, morningstar, nunchaku, spiked chain, and whip.
Hammers: club, light hammer, light mace, greatclub, heavy mace, and warhammer.
Monk: kama, nunchaku, sai, shuriken, siangham, and unarmed strike.
Pole Arms: glaive, guisarme, halberd, ranseur, and quarterstaff.
Spears: javelin, lance, longspear, shortspear, spear, and trident.
Thrown: bolas, club, dart, dagger, handaxe, javelin, light hammer, net, shortspear, shuriken, sling, spear, and trident.
Weapon Mastery (Ex)
At 20th level, a fighter chooses one weapon, such as the longsword, greataxe, or longbow. Any attacks made with that weapon automatically confirm all critical threats and have their damage multiplier increased by 1 (a ×2 becomes a ×3, for example). In addition, he cannot be disarmed while wielding a weapon of this type.