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
Pioneering six-degrees-of-freedom shooter through robot-infested mines.

Execution · Practiced Mastery
An encyclopedic driving simulator spanning 700 cars and decades of automotive history.
Descent leans Execution (Practiced Mastery); Gran Turismo 4 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.
Descent
Full 6DOF control and aim under disorientation is the test
Gran Turismo 4
Hundreds of cars all demand precise inputs
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Descent
Scripted robot behaviors, no adaptation
Gran Turismo 4
Fixed-line AI offers no adaptive opposition
Descent leans a little harder on variance, though the gap is small.
Descent
Mine layouts fixed; ambushes surprise only once
Gran Turismo 4
Deterministic outside slight tyre wear modelling
Gran Turismo 4 leans a little harder on optimization, though the gap is small.
Descent
Route memorization and weapon economy reward optimization
Gran Turismo 4
Event-by-event car and tune selection is deeply 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.