I don't disagree with your points here, other than the MOT changed in May to include inspection of the DPF system if fitted (on 2006 onwards vehicles) , includi

I don't disagree with your points here, other than the MOT changed in May to include inspection of the DPF system if fitted (on 2006 onwards vehicles) , including checking for one which has been cut open. Obviously not foolproof, but at least its a start - if the DPF is missing, it's a fail now.