A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from the Wayback Machine (its copy), so posts it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
A player, 1 April 2005
Bayushi Muhito
Reaction: Once per turn, after Muhito moves during an Attack Phase, take a Battle or Open action
Muhito's ability doesn't produce a meaningful effect outside of the Battle Action Segment. It does not allow you to take Battle or Open Actions outside of designated Segments / Phases in which you are allowed to do so. You can't take Battle or Open Actions during Maneuvers or Resolution segments of a Battle.
From the rulebook p77 :
4. ATTACK PHASE (OPTIONAL)
This phase has five segments:
1. Declaration Segment
2. Infantry Maneuvers Segment
3. Cavalry Maneuvers Segment
4. Battle Action Segment
5. Resolution Segment
From the rulebook p34
Cardinal Rule
If any card or Stronghold explicitly contradicts these rules, the card or Stronghold takes precedence.
I would like to know the reason why Muhito doesn't create an opportunity to play a Battle action or Open action, aven outside the Battle action segment. The card contradicts the rulebook, so takes precedence no? Even during maneuvers or Resolution, are we not still in the attack phase?
Martin Lund (rules official), 1 April 2005
Bayushi Muhito
Reaction: Once per turn, after Muhito moves during an Attack Phase, take a Battle or Open action
From the rulebook p77 :
4. ATTACK PHASE (OPTIONAL)
This phase has five segments:
1. Declaration Segment
2. Infantry Maneuvers Segment
3. Cavalry Maneuvers Segment
4. Battle Action Segment
5. Resolution Segment
From the rulebook p34
Cardinal Rule
If any card or Stronghold explicitly contradicts these rules, the card or Stronghold takes precedence.
I would like to know the reason why Muhito doesn't create an opportunity to play a Battle action or Open action, aven outside the Battle action segment. The card contradicts the rulebook, so takes precedence no? Even during maneuvers or Resolution, are we not still in the attack phase?
Does he say, "Even during X" where X is a place it is not normally legal to take an Open or Battle Action?
No.
Is it never legal to use his ability in a place with Open and Battle Actions are legal?
No.
Then he doesn't break the rule prohibiting you from taking a particular kind of Action outside of its designated Phases / Segments.
The same thing goes for Ciphered Scroll not letting you cast a Limited Spell during the Battle Action Segment, which you can see in the March Archives here.