If you have 100 strength and use a greater strength potion, will the increase apply to damage bonuses for combat past 100? And do bonuses past 100 from accuracy bonuses on weapons apply to anything?
#1. Yes. You will get a damage bonus, though I'm not sure if there is a table out there somewhere that lists it. #2. Yes. This also provides a damage bonus. Again, I'm not sure if there is a table out there that lists it (as the bonus damage out there would be different depending on the weapon you are using).
For STR, every 5 points is worth 1% bonus, so the potion of strength is worth about 4% more damage. For Tactics bonuses, every 5% bonus is worth 5% more damage.
