head to head
DiRT 4 asks more than Half-Life 2, and the gap is variance.

Execution · Pure Mechanics
A rally sim whose procedural stages keep variance alive while rewarding clean car control.

Execution · Pure Mechanics
Landmark FPS built on physics puzzles and tight gunplay.
DiRT 4 leans Execution (Pure Mechanics); Half-Life 2 leans Execution (Pure Mechanics).
DiRT 4 leans clearly harder on execution.
DiRT 4
Procedural stages still demand consistent throttle and apex discipline
Half-Life 2
Gravity gun and shooting demand precision.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
DiRT 4
Time-attack structure has no adaptive opponent
Half-Life 2
Combine AI scripted, non-adaptive.
DiRT 4 leans clearly harder on variance.
DiRT 4
Procedurally generated stages prevent full route memorisation
Half-Life 2
Almost no randomness.
DiRT 4 leans clearly harder on optimization.
DiRT 4
Car choice, setup and rally team progression are solvable systems
Half-Life 2
Linear progression with no builds.
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.