head to head
vs
Portal 2vsSpaceChem
Portal 2 leans Optimization (Pure Optimization); SpaceChem leans Optimization (Pure Optimization).
Portal 2SpaceChem
Axis by axis
Execution3 vs 2
Portal 2 leans harder on execution: Portal placement requires some precision but timing is lenient.
Reads0 vs 0
Even - both lean on reads about the same.
Variance0 vs 0
Even - both lean on variance about the same.
Optimization9 vs 10
SpaceChem leans harder on optimization: Designing correct chemical pipelines that transform inputs to outputs exactly
Two games can score the same on an axis and still test it in very different ways - read each rationale, not just the number.