I have been waiting ages for this can of worms to surface. Along with many others here,I am totally against removal of DPFs even though there are undoubtedly problems in reliable operation.
We,as an Industry, should not be removing an emissions device and altering software to hide the fact that we have performed this operation which considerably adds to the pollution emitted by that vehicle.
Making this illegal is just a start, policing it is going to be the real problem on cars already without DPFs, but if WE as an industry refuse to do it,-as we should-because it is illegal, then policing the remaining 'cowboys' should be easier.
I do MSA scrutineering in my spare time, and a couple of years back the MSA came out with all racecars (late ones) had to be fitted with CATS, not that we checked emissions or lambda, just that if it looked like a CAT then that's it, hopefully we can do better with this.
In most situations- even a free standing max revs check will give some indication of soot at the back when DPF has been removed. To suggest that 'turning back' the fuelling with any tool and altering the subject line of this thread is a joke which shows a complete disregard for how important this issue is.