First off forgive me if this has been raised before. While reading through Desertfall, I came across this passage on determination usage:
Automatic 1: Before rolling, choose one of the d20s in your dice pool: that die is considered to have rolled a 1, and does not need to be rolled. It thus scores a critical success automatically.
In Star Trek Adventures we have this approach (referenced from the Klingon Core book):
Automatic Successes: You can spend 1 Determination to add a single bonus d20 to your dice pool that has already rolled a 1, generating 2 successes automatically. This must be the first d20 you buy using either Determination or Momentum.
The primary difference here is in Dune we change the result of a pool D20 to a 1, in STA we add one die to the pool with result 1.
Is this a known difference in Determination mechanic between the two games?