It's a simple card. You really can't go wrong using this to get extra uses out of Unrelenting or Seal of the Elder Sign, as long as your deck is relatively skill heavy. Every other effect it has is pure gravy.
Using it as a retroactive commit tool makes it a variant of Lucky: 0 cost, but requires you to spend a card. The 0 cost is also excellent for Dark Horse decks. If you retroactively commit a cantrip skill (Perception, Overpower et. al), the card cost will be offset. If you're only short by +1, retroactively committing Unrelenting allows you to draw 2 card without the sealed tokens affecting the test result. Using it to commit events or assets is meh, but sometimes you just need to pass that test. If you drew though, not much will help save for a retroactive Take Heart or Seal of the Elder Sign.
The Grisly Totem/Try and Try Again effect if you fail and is always useful, except that this can be used on allies as well. Winifred will love you for saving that All In from being wasted on an . And you can recover the card even if you don't fail the test. Take back a wasted Take Heart or Last Chance after you draw your or a , or an Unrelenting for 2 more cards, or a Signum Crucis for even more blessings. If Agnes takes back that Seal of the Elder Sign: you'll no longer be getting an effect on this test, but no chaos token is revealed anyway.
It's not an auto-include by any means. Although Silas, Pete and Minh run skill heavy, their deck slots tend to be highly contested, and unless they're doing bless tech it's likely to be less effective than a Try and Try Again. The idea use case is to support a skill heavy ally while also being skill heavy yourself.