If you have the expansion, when you're in the abbey of Hiram, you can "speak" to the fountain in the center of the abbey. It costs 20,000$ to respec. It is useful though. For example, you may want to start the game with Lightning Precision (Lucas) until you can invest some points into "Wind Shear" bleeding ability later. Then, with easy bleeding, you may end wanting Hemorrhage instead. Now this can be done. Same goes with Graceful Repose. You may want the retribution bonus to it at first, but then once mastered and once allies can benefit from it, you may prefer Live by the Sword, etc.