The whole darkness thing came from a study that was done a while back, they found one particular pheno of a particular white strain that had a noticeable increase in trichs when left in a climate controlled room for 3 days of uninterrupted darkness, if it got any light it wouldnt happen, they tried it on other white strains and it didnt do anything, just that single pheno of the strain. Dont remember the strain. I know people who live by it but I see no difference in their stuff when they do it.