My problem with this is that when you have been working on an assembly for 2 days, you may tend to overlook something that you would have seen otherwise. There will be no checks and balances.
How many times have you been working on something and think you have it just right and someone else looks at it a immediatly notices a problem that is as plain as day???
Yes a production worker can check his own work, and sign off on his own work, but not sign off for final acceptance. This is wrong!