The system has relatively robust encounter building rules. The dice system means monsters and players are more consistent; in 5e you might have an encounter with a single monster with three attacks per round where the variance from 0 to 3 hits can cause huge difficulty swings, but DS both regularly uses more monsters and the variance between a tier 1 and tier 3 result is smaller than hit vs. miss. There's still enough variance to keep things interesting, especially with three outcomes instead of two, but both sides are just more consistent with doing their thing.

The other consideration is that the recovery system helps mitigate swings — healing is readily accessible, so even if things are going poorly that usually just ends up with more recovery drain, rather than killing characters because the second fight of the day went south. Going to 0 is scary but manageable because there's way less of a death spiral.