head to head
vs
Left 4 DeadvsSnowboard Kids
Left 4 Dead leans Execution (Twitch Chaos); Snowboard Kids leans Execution (Practiced Mastery).
Left 4 DeadSnowboard Kids
Axis by axis
Execution7 vs 6
Left 4 Dead leans harder on execution: Headshots, melee shoves, and special-infected reaction time
Reads2 vs 2
Even - both lean on reads about the same.
Variance5 vs 4
Left 4 Dead leans harder on variance: AI Director randomizes hordes, items, and specials
Optimization5 vs 5
Even - both lean on optimization about the same.
Two games can score the same on an axis and still test it in very different ways - read each rationale, not just the number.