head to head
Neither is simply harder - they are hard in different places. Portal 2 demands more execution; Pro Cycling Manager 2014 demands more variance.

Optimization · Pure Optimization
A first-person puzzle game where seeing the solution is the whole skill.

Optimization · Pure Optimization
A cycling management sim about running a professional cycling team through races.
Portal 2 leans Optimization (Pure Optimization); Pro Cycling Manager 2014 leans Optimization (Pure Optimization).
Portal 2 leans clearly harder on execution.
Portal 2
Portal placement requires some precision but timing is lenient.
Pro Cycling Manager 2014
no direct physical control, management sim
Pro Cycling Manager 2014 leans a little harder on reads, though the gap is small.
Portal 2
No opponent; puzzles are static.
Pro Cycling Manager 2014
rival team strategies vary slightly
Pro Cycling Manager 2014 leans clearly harder on variance.
Portal 2
Puzzles are deterministic with no randomness.
Pro Cycling Manager 2014
weather and race incident randomness
Portal 2 leans a little harder on optimization, though the gap is small.
Portal 2
Solving the puzzle's logic IS the entire game.
Pro Cycling Manager 2014
training, tactics, and race-plan mastery
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.