People have wildly different reactions, some of my friends can take 14g+ and be fine, others are barely able to talk after 2g. Plus potency varies wildly between crops and strains.
Also, there are different types of shrooms, saw at least 7 types last in Amsterdam, potency varied significantly. Also, how empty your stomach is makes world of difference. Also, method of consumption - dried vs fresh, raw/cooked, or like me mixing it with raw lemon juice (makes trip shorter but way more intense - 3g trips were full beyond reality with good setting).
Plus individual variation in digestion/enzymes/receptors/god knows what else is most probably also important.
