Don't forget. (Calculations.)

[Juigi Kario]

1) The weapon triangle boost is actually +5 or -5 with a multiplier based on whether or not the advantaged person's weapon rank is C or above. (It's 2 when that's the case, otherwise it's a measly 1.)

2) Weapon triangle advantage actually provides an attack boost of 0.5 with a similar such multiplier. Of course, I believe the multiplier is 0 when the disadvantaged person already has an A Rank for their equipped weapon.

Oh, don't worry about giving me credit for the other findings of mine that I posted in here, I think it's safe enough to say you found the information on your own if you didn't talk about these tidbits. (You did at least find out the Tome boosts. That's useful.)