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

Execution · Practiced Mastery
A grittier crime story where weighty driving and gunplay carry the experience.

Execution · Pure Mechanics
Island-themed collection of twelve motion-controlled sports showcasing the Wii MotionPlus accessory.
Grand Theft Auto IV leans Execution (Practiced Mastery); Wii Sports Resort leans Execution (Pure Mechanics).
Wii Sports Resort leans a little harder on execution, though the gap is small.
Grand Theft Auto IV
Heavier driving and cover shooting reward control.
Wii Sports Resort
MotionPlus precision in swordplay, archery and bowling
Wii Sports Resort leans a little harder on reads, though the gap is small.
Grand Theft Auto IV
Scripted AI, no adaptive opponent modeling.
Wii Sports Resort
Local versus duels involve mild feinting
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto IV
Minor mission variance.
Wii Sports Resort
Slight physics and CPU pattern randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto IV
Mission routing and weapon picks learnable.
Wii Sports Resort
Each event has small learnable technique optima
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.