Chikahiro Tokoro's practical advice for tackling God objects: don't refactor for refactoring's sake and don't do big-bang rewrites. Find a concrete upcoming business goal (e.g. 'we need single sign-on for a new app') and use it as the excuse and scope for extracting responsibilities. Slice features for incremental business wins (e.g. first let an order track multiple shipments, then let a basket produce multiple orders) so each step is easy to sell internally and cheap to ship.