Back in Patch 1.05 for D2, there was a balance change that the Paladin Concentration skill enhances the damage of Blessed Hammer. Concentration has a hidden effect and increases the damage of Blessed Hammer by 50%. With the developers updating the tooltips for all the skills in Balance Patch 2.4, it would make sense for the corresponding tooltip to be updated to show the hidden synergy for added clarity.
Back in d2 classic Blessed Hammer(at least until 1.06) was blockable (not sure if it required attack rating id have to launch the older patches and im lazy).
And it was boostable not just by Concentration but by Might as well.
Even all the way until Patch 1.09(that’s well into LoD) but in Classic d2 only(that is Classic 1.09) your lying character screen would show that Blessed Hammer deals increased damage if you have both Might+Concentration on even though by that point it was only affected by Concentration .
The point im trying to say is for whatever reason it was affected by dmg auras…maybe blizzard at some point coded it to be a phyiscal damage spell since it was blockable and then changed it at the last minute?
Whatever their intention was the Conc aura is definitely a bug or at least an unintended effect.
This is not meaningless spam, but a recommendation to the devs to update the tooltip for the hidden synergy of concentration on blessed hammers. They’ve updated most tooltips in the game, looks like they missed one.