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
Pure car control over loose surfaces, sharpened by memorising every stage.

Execution · Practiced Mastery
Combo execution layered over solving each park's optimal scoring line.
Colin McRae Rally 2.0 leans Execution (Pure Mechanics); Tony Hawk's Underground 2 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.
Colin McRae Rally 2.0
Surface-specific car control at speed decides every stage
Tony Hawk's Underground 2
Combo timing, balance meters and manuals demand practiced hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Colin McRae Rally 2.0
Time-trial format - no adaptive opponent on the stage
Tony Hawk's Underground 2
No opponent adapts; score attack is solo
Colin McRae Rally 2.0 leans a little harder on variance, though the gap is small.
Colin McRae Rally 2.0
Mid-stage surprises minimal once pace notes are internalised
Tony Hawk's Underground 2
Maps and goals are fixed and fully knowable
Tony Hawk's Underground 2 leans a little harder on optimization, though the gap is small.
Colin McRae Rally 2.0
Memorising stages and tuning setups converges times steadily
Tony Hawk's Underground 2
Finding the highest-scoring line through each park is solvable
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.