head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Execution · Pure Mechanics
Landmark FPS built on physics puzzles and tight gunplay.

Execution · Pure Mechanics
A motion-control party collection testing full-body timing and little else.
Half-Life 2 leans Execution (Pure Mechanics); Kinect Sports: Season Two leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Half-Life 2
Gravity gun and shooting demand precision.
Kinect Sports: Season Two
Full-body motion timing is the entire skill surface
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Half-Life 2
Combine AI scripted, non-adaptive.
Kinect Sports: Season Two
Party opponents barely reward prediction
Kinect Sports: Season Two leans a little harder on variance, though the gap is small.
Half-Life 2
Almost no randomness.
Kinect Sports: Season Two
Sensor reading adds unintended noise
Half-Life 2 leans a little harder on optimization, though the gap is small.
Half-Life 2
Linear progression with no builds.
Kinect Sports: Season Two
Minigames have little system depth to solve
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.