OK, here are the relevant quotes:
Page 52, under Frenzy :
"Frenzied models fight with +1 extra attack during close combat."
A man on a horse in one model. Thus, the model as a whole gets +1 attack.
"Models that have one attack on their profile therefore have 2..."
A profile can contain more than one statline, that of the rider's and that of the steed's. Thus, the profile gets +1 attack, not each statline on it.
Page 78, under Characters, under Mounts' Psychology :
"This means that all parts of the model (a monstous mount, or the crew and steeds pulling a chariot) are affected by these rules [i.e. frenzy]."
So, when a character is on a monstrous mount, or in a chariot, everyone gets +1 attack. But this only applies to characters, and not when they're on horses - so not to Khornate Knights.
So, basically frenzy is the same as it's always been, but now dragons, hippogryphs etc will get +1 attack aswell.
i wszystko jasne
