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.
If I target a Personality carrying an Item with Tametaka XP's ability to reduce its Force to 0, what happens? Is the Personality treated as having a printed Force of 0 with the Item still giving its bonuses, or are the item's effects reduced to 0 as well?
What if I use the ability on a card that's gained a Force bonus from some other card ability?
Printed force never changes, it's the number physically written in ink on the card (or on the ability that created the card, if it's a created card). That's why it's called "printed" and not "current". The Personality not only "is treated as" having zero force, it *effectively* has zero force. The bonuses from the items still apply, however your problem is that a big force penalty is also applying.
If, for example, you have 4F Personality with a Wyrmbone Katana (+4F), the Personality would have 8F. Then Tametaka reduces the force to 0, which effectively means giving him a penalty of -8F.
So your personality has: 4F (Printed) +4F (Wyrmbone katana) -8F (Tametaka XP) = 0F
The Item's force is still there, the personality's printed force didn't change, it's the big penalty created by Tametaka XP the reason of your loss of force. See Setting Stats to a value in the CR:
To set a stat to a value, give it the smallest possible appropriate bonus or penalty (or the smallest possible gain or loss, for Honor) such that it would reach that value, not counting any maximum or minimum in effect for that stat. Effects that “raise,” or “lower,” a stat to a particular value use these rules as well, but will only give a bonus (“raise”) or penalty (“lower”).