Heliport
Unless things have changed, there is no real point in handcuffing someone unless they are puchy or lightly to do a runner. I doubt that was the case in this incident, but then I wasn't there, and in anycase as you say it's pure rumour at the moment. If it did happen it does seem over the top, however they may have been reasons.
To clarrify. Obviously if you have had nothing to drink, then you have no problem. If you have had less to drink than the prescribed limit, again you have nothing to worry about. So the goalposts have not moved, I just perhaps could have phrased it better.
I accept that arrest is for most people a very unusual experience, and probably worrying. Especialy when your livelyhood is on the line. But then thats the idea of having legislation like this, not to catch people out, but to deter them from doing it in the first place. The screening breath test machines are not considered accurate enough for evidencial purposes in court no, but I have to say since they came out, I had only one person come back under the limit on the evidencial machine, after a positive test on the screening device. As you rightly say the 'error' works both ways, I think the screening device probably leans more towards the lower end.
Of course there is a delay bewteen the screening test and breath test or blood sample being taken at the police station. During this period it is perfectly possible that BAC can dip below the line had it been very close to the limit at the time of the screening test. So although a sample may be below at the police station it does not mean that arrest was unjustified or that the person was not over at the time of the screening test.
Zippy2004
Your correct they probably wont, but then thats not confined to aircrew. The chap from REM was charged with offences on an aircraft and cleared by a jury. There was no retraction in that case.