Driving more nails into the Schengen coffin

It's not France and Italy this time, but Denmark, driving more nails into the coffin of Schengen, Europe's border free system, at least in spirit. Danish Finance Minister Claus Hjort Frederiksen, as reported by BBC, said:
We have reached agreement on reintroducing customs inspections at Denmark's borders as soon as possible
This is the centre-right administration in Denmark relying on support from the Dansk Folkeparti. The BBC report claims that the new controls will not breach the Schengen rules. This means that these checks are not regular border controls, and hence will take place in Denmark only. This may seem like an academic distinction, but to use the example from Brenner, the check would have to take place after the border. This - for those that know Copenhagen - would mean that Öresund trains would be boarded by guards at Kastrup, for checks between there and Main Station. Road checks would have to be somewhere on Danish soil, and the minister's statement about new electronic number plate reading technology might actually mean they do not stop all cars anyway...
Furthermore all of this gets complex is that Denmark does not have an obligation to show identification to a police officer. As a Dane you only have to state a name and an address, and they can - with reason - ask for a personal number. The answer from a train passenger could just be 'oh I got on at Kastrup', whereas the person actually came across the bridge from Malmö. Furthermore the sheer scale of checks - there's a train every 10 minutes at peak between Malmö and Copenhagen, and a busy dual lane motorway - would require administration (and delay to road passengers) of an enormous scale. It will hence be interesting to see how much of this actually comes to pass.
Then there is of course the open question as to whether border controls actually work anyway... but of course if you're a right wing party facing elections this autumn then a small issue like that isn't going to matter to you. Having said that, however the practicalities work out, today is a sad day for the spirit of Schengen.
Photo: greg92_09 2 “DSBFirst 4374” January 2, 2010 via Flickr, Creative Commons Attribution