head to head
DiRT 4vsThe Callisto Protocol
DiRT 4 leans Execution (Pure Mechanics); The Callisto Protocol leans Execution (Pure Mechanics).
DiRT 4The Callisto Protocol
Axis by axis
Execution8 vs 8
Even - both lean on execution about the same.
Reads1 vs 1
Even - both lean on reads about the same.
Variance4 vs 3
DiRT 4 leans harder on variance: Procedurally generated stages prevent full route memorisation
Optimization5 vs 5
Even - both lean on optimization about the same.
Two games can score the same on an axis and still test it in very different ways - read each rationale, not just the number.

