Shield Oath doesn't reduce damage by 25%. It does take 25% more damage to kill one in shield oath, but that's a different story.
Hallowed Ground being described as "immortality" isn't correct. Holmgang would fit closer to the description of immortality as they're still taking damage, but do not die as the effect is in place.
Holmgang doesn't always bind the target if said target is immune. It does root the user to it's current position, however.

Some inconsistencies such as DMG or DD and some skills having untraited/traited references (Convalescence for example) while others are listed as traited by default