If 8-level fighter has Weapon Focus (longsword), Weapon Specialization (longsword) and takes Melee Weapon Mastery (slashing)as his 8-level feat, his attack bonus for e.g. battleaxe would be +2 as per the feat. His damage bonus would be also +2. But what are the bonuses for longsword-attack +3/damage +4? Or just +2/+2 as with all slashing weapons? And what about Greater Weapon Focus/Specialization-will they stack also with this feat?