Because since you get a permanent affinity at the end of S2 (or even early, if you constantly did CHICK or DIK choices in a row) with Neutral affinity you always have a "Neutral" option and the other one (DIK or CHICK) is shaped according to your previous behaviors. If you've been fighting a lot - you'll always have an option to "punch" someone (Oscar, Vinny). But even THIS options depends on specific conditions. You need to fight with ALL (Both with Jocks AND Tommy) to be able to punch Vinny. While conditions to punch Oscar is less strict (you have to fight with only one of them - Jocks/Caleb/Tommy). It's probably for the good in Vinny's case, but it also blocks you in Patrick & Maya scene... you can't "save" Maya if you're Neutral and a "fighter". Same goes to drugs. if you ended up with Jill, have a Neutral affinity and smoked weed with Quinn back in EP4, your choice of doing shrooms in EP10 will work the same way - you will always have a Neutral choice, but Chick or DIK option will depend on how you behaved previously. You'll be able to eat shrooms if you smoked weed. This will lead to an extended scene with Jill at BBQ party and also will lead to an addtional choice (to give her a promise not to do it again, or not to give her such a promise). Neutral aff is quite exciting in terms of MC personality shaping and getting very specific scenes and outcomes, while being on the "edge" of almost impossible conditions.