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, 11 April 2013
Not entirely sure on the proper interaction of Isawa Kojiro and Manipulate Energies.
Isawa Kojiro has a spell attached and thus the Naval trait. Kojiro is then targeted by Manipulate Energies and the player chooses to remove the Naval trait from Kojiro.
What happens?
Does Kojiro lose Naval forevermore regardless of what happens to his spell count?
Does the trait go away but then come back straight away as the trait on Kojiro is an ongoing check and he still has a spell so the trait reappears?
Does it go away until Kojiro attaches another spell?
Paul Ashman
A player, 12 April 2013
What happens?
For starters, he loses his current Naval keyword
Does Kojiro lose Naval forevermore regardless of what happens to his spell count?
No. See below.
Does the trait go away but then come back straight away as the trait on Kojiro is an ongoing check and he still has a spell so the trait reappears?
Kojiro isn't an ongoing but a continuous effect. This is quite relevant because you're not "stopping" the trait: it's still working as long as Kojiro has spells attached - any number of them. Attaching more spells to Kojiro won't help because Kojiro reads:
Kojiro has Naval while he has a Spell.
The condition will be true if he has one spell, and still will be true if you attach a second one. Since the trait will work without interruption, the loss of Naval will linger.
However, if at any point Kojiro loses all his spells, the trait will stop working. Then, attaching another Spell to Kojiro will make Kojiro's trait restart and he'll gain Naval again.
See the rules for continuous effects (I'm quoting also the example because it is quite ilustrative): If another effect reverses or modifies the continuous effect, the continuous effect does not automatically re-assert itself. Only if the continuous effect ends and begins again, or if the other effect ends, would the continuous effect begin. Example: An effect on one of your Holdings in play states “Your Human Personalities are Samurai while they are opposed.” If another effect removes the Samurai keyword from one of these opposed Personalities, your card’s effect does not give him back Samurai immediately. However, if your Holding leaves play and re-enters play it would re-apply Samurai to all your opposed Human Personalities, including the one who had Samurai removed. Also, if your Samurai was no longer opposed, and then became opposed again, he would regain Samurai.
The first sentence explains why adding new spells doesn't help. The second sentence explains that ending and then restarting the trait would help, though.