Another answer might be "effective". One might argue that Okinawan empty hand kata contain some movements that provide for effective use of a spear-like weapon.
And yet another answer might be "very effective". One might argue that Okinawan empty hand kata contain many movements that provide for effective use of a spear-like weapon.
I think some of the spear hand striking attacks and strikes using the blade of the hand could certainly be adapted if one was carrying a spear or a sword.