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
Open-world racing testing car control and line discipline with light tuning underneath.

Execution · Practiced Mastery
A snowboarding sim testing trick execution and line selection for high scores.
Forza Horizon 2 leans Execution (Pure Mechanics); Mark McMorris Infinite Air leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Forza Horizon 2
Racing lines, braking points and car control lead everything
Mark McMorris Infinite Air
Trick timing, rotation and landing control define runs
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Forza Horizon 2
Drivatar AI mimics styles but stays effectively scripted
Mark McMorris Infinite Air
Solo and scored runs, no adaptive opponent
Mark McMorris Infinite Air leans a little harder on variance, though the gap is small.
Forza Horizon 2
Weather shifts grip slightly; courses are fully known
Mark McMorris Infinite Air
Procedural terrain adds some unpredictability
Mark McMorris Infinite Air leans a little harder on optimization, though the gap is small.
Forza Horizon 2
Car tuning and route knowledge reward preparation
Mark McMorris Infinite Air
Trick chaining and line selection optimize scores
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.