Dunno if you've ever heard of the Hay diet - (for people) - they eat protein only one day and carb only the next- supposed to allow the body to digest food better. Now while cats aren't really supposed to eat carbs there are carbs in the biscuits so lets consider them to be the carb meals- and they do "bulk up" in the tummy like slimfast so it stands to reason to try and make sure that he waits at least a few hours between meal types so he can digest things properly. I know with a BARF diet it takes a particularly long time to digest so if I feed raw I feed it for breakfast (or all day) rather than after biscuits as I'm pretty sure it'd cause problems, at the very least flatulent animals!.