This thread is going around in circles, so I'm now locking it after my post.
The way the DWP currently collate statistics means they cannot really differentiate between actual fraud, official DWP error and failure to report a change in circumstances.
DLA actual fraud is less than 0.5% as has been confirmed by a DWP Fraud Officer who Jim keeps in touch with. Plus a survey carried out fairly recently by the DWP's Social Policy Unit found that there was an under claim of 40% for DLA claims.
I think these figures speak for themselves.
More here
Benefit Fraud Figures