It's not 12% extra damage iirc. It's 22%. GL3 = 27% damage alone, Twin Snakes is 10%, Fists of Fire is 5%. The statement 'NIN has their own TS by slashing resistance...' no. That's not how resistances work. Yes, you should count Twin Snakes. Why wouldn't you? Really. MNK gets Blunt resistance down (6-7%) via Dragon Kick ON TOP of a flat 10% damage increase. NIN only Venom at 20% with slashing which is 6-7% damage.

Bootshine is an autocrit, have to account for that too.