Martial Mastery

Martial Mastery is a passive AS boost that incentivizes training in multiple weapon types and is an alternative to going for 425. This bonus requires training 2x in a primary weapon skill, and is lost entirely at known 25 spell ranks. These restrictions effectively limit the bonus to squares.

AS Bonus = FLOOR(Secondary Weapon Ranks / Tertiary Weapon Ranks) / 8)

Spell Penalty = FLOOR(MAX(0, (AS Bonus - ((AS Bonus * (25 * 5)) / 100)))

Secondary and Tertiary weapon ranks are the weapons you have the most training in after you primary weapon skill.