hobby fascination disorder
n. condition that consumes one's character to the point of analyzing the substance, validity and quantity of their hobbies and moreover the hobbies of others. Extreme cases include "I've got more hobbies than you and they are better than yours" tantrums and reaching hobby goals of several new hobbies a week to secure the "I've got more hobbies than you and they are better than yours" quarrel. No cure exists for these hobbyist due to the developmental issues that plague the brain in a constant, old hobby, present hobby and future hobby beat that never finds closure.
Don't pet him, he's got hfd(hobby fascination disorder.