Do Companies House check accounts filed?

Haven't heard from a small Limited Company client for a while and date for filing accounts well past, so I thought I'd check Companies House, just in case. The client has obviously cobbled something together themselves which is riddled with errors. I'm amazed to see that it is stamped by Companies House as received in September 2005 so presumably they've accepted them. What's the point of sweating over Company Disclosure checklists if a pile of garbage masquerading as a set of accounts is accepted?
Andrew