Let's first start by verifying that there actually exists such behaviour - there are no citations for larvae lifecycle part in Wikipedia and I couldn't find any

Let's first start by verifying that there actually exists such behaviour - there are no citations for larvae lifecycle part in Wikipedia and I couldn't find any reference in papers. Maybe larvae just consumes a little of every organ it can get to. The whole story about it consuming non-essential organs first seems quite fishy - how many of those do cockroaches have anyway? Even if that's true, after eating away few organs you pretty sure to get organism failure no matter what order. Doesn't seem very smart strategy to me.