6. Edition Blödheit einzelner Charaktere in Einheit

Q. If a character that is suffering stupidity is part of a unit that is
not stupid, does the character force the unit to stumble forwards, or
does he leave the unit, allowing the unit to operate as normal?

A. The entire unit stumbles forward at half the character's movement
value or the unit's base movement value, whichever is lower.
S. Anthony Reynolds - Warhammer Design Team (Online Q&A on the
Games Workshop Warhammer Forum)

🙂