The answer to your question is that you now seem to completely understand that activating the stance and then subsequently using it causes any particular melee attack to cost one more action point. Is it a bug? No. Is it a misunderstanding of the text? Absolutely.



Note that D:OS is not the only AP-combat game to use such a mechanic. Fallout is the first one that I can remember, where you could selectively exchange more APs for better accuracy (and maybe more damage, I don't recall). Jagged Alliance probably uses it, as well, but I don't remember for certain. Similar concept, but D:OS made it a skill instead of simply a right-click option. The idea is that you're taking more time to either A) steady your aim / wait for their guard to drop, or B) you're winding up for a big ol' roundhouse. Either way, a special stance (better accuracy / damage) costs more AP and you get some specific benefit for activating and then using it.

Now, the reason why we said that activating the skill doesn't use any action points is because it doesn't use any action points. I just activated and deactivated the accuracy version (Melee Precision Stance) 9 times, once for each AP that this particular character has at the beginning of combat, and it didn't expend a single one of those APs. When I finally attacked with it activated, that's when the melee attack used an extra point - just as the skill description says it will. In exchange for that AP, my % to hit went from 78% to 100%. Again, just as the description says it will.

The text is correct, and there is no bug.