A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages 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, 2 December 2007
does this allow me to target my opponents focus pool or only my own? Red Leaf Cut Cost:
0 Focus:
2 Reaction: Before Focus Effects resolve: Discard a focused card; its owner may focus an additional card from his hand or focus pool. Reaction: After a Battle action resolves: Give -3F to a target Personality who performed it.
Zen Faulkes (rules official), 2 December 2007
does this allow me to target my opponents focus pool or only my own?
Point: It does not target.
All that is required is "a focused card." It does not specify who focused it.