WTF are you talking about. Warrior's guild is like 90% of a warrior's power. Berserk, Wtrick feint, Warcries are all staples especially at the 6.3 levels at mastery.
How is it a constant? Bards don't have a guild, no empath guild or pure guilds worth anything. Rogues have a guild but are much less crucial to the class' power than warriors.