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 · Practiced Mastery
Coordinating two-man cover tactics and aggro swaps through scripted firefights.

Optimization · Practiced Mastery
A tactical police shooter where careful, methodical tactics against randomized threats defines mastery.
Army of Two: The 40th Day leans Execution (Practiced Mastery); SWAT 4 leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Army of Two: The 40th Day
Cover shooting needs competent aim but generous systems forgive
SWAT 4
precise aim and careful movement required
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Army of Two: The 40th Day
Enemy AI is scripted, co-op partner cooperates rather than opposes
SWAT 4
suspects react but don't truly adapt
SWAT 4 leans a little harder on variance, though the gap is small.
Army of Two: The 40th Day
Encounters are scripted with minor spawn unknowns first time
SWAT 4
suspect placement and behavior randomized
SWAT 4 leans a little harder on optimization, though the gap is small.
Army of Two: The 40th Day
Aggro management and weapon upgrades reward planned coordination
SWAT 4
tactics and equipment loadouts 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.