either you or UO.com is wrong
How to Use:
Similar to the mage’s Meditation skill, Battle Focus will raise passively as you regain Stamina and Mana. You simply need to do anything that lowers your Stamina and Mana in order to increase the level of your skill.
it also says the same thing on uoguide.com
maybe it is fixed now but this is or at least was a bug and if nothing else be acknowledged as one. If you want the players to find and report bugs, then don't dismiss them so easily or make the player prove how/why/what color/ time of day. I get that information helps but …..