I have never been visited by the boys in blue, regardless of whether or not I filed the GARs. I suspect they have far more worth while matters to which to attend.
I've been met on three occasions.
First one everything was ok, just local plod was asked to attend by SB. They collected the same details that I'd already provided on the GAR, and offered tourist advice
Second one was because I gave notice to South Wales police force rather then North Wales police force. Despite the fact that I'd given 2 weeks notice, noone had bothered to either call me back and inform me of my error, or forward the GAR to the correct agency. North Wales Police force tell me that they have a policy of attending EVERY SINGLE arrival that is subject to a (correctly filed) GAR.
Third time was "call Special Branch on arrival". I got 'informed' of my obligation to file a GAR, and the SB officer demanded to know why I hadn't. When I advised I had, they took no heed of this simply stateing that they'd no record of it. The grumpyness stopped when I produced the fax confirmation page, and suddenly it wasn't a problem anymore.
Other police forces it's obvious that they couldn't care less about them.
There is no consistancy across the UK. (Why do you need so many different police forces???) Some police forces seem to think they are a total waste of time and couldn't be bothered with them, while others make a full time job (for several people) and visit every arrival/departure
dp