BAA did well to get approving articles on the latest security upgrade at its airports into weekend newspapers.
Last Saturday's Financial Times ran a substantial piece under the headline "BAA moves to speed up security checks". No doubt this attracted the eye of weary corporate travellers - although the Monday editions might have made more sense when passengers could have read it as they passed through Heathrow and glimpsed light at the end of the tunnel.
Forgive me, then, for pouring cold water on the latest enhancement to airport security behind the headline - the handheld vapour detector.
Two hundred of these will be deployed "to sniff out substances used in home-made bombs", according to the FT.
Leave aside the fact that dogs and people sniff and most handheld devices do not, these vapour detectors will "add an extra layer of safety", says BAA, as part of a roll out of equipment intended to ease carry-on baggage restrictions.
The Ion Mobility Spectrometry (IMS) technology will test passengers' luggage for traces of explosive material without the need to take a swab for a litmus test. The handheld IMS test will take as little as 10 seconds, which is good.
But the detectors will be used when passengers have already been stopped for a hand-luggage search to identify any liquids or traces of liquid. The detectors will speed up the experience of those detained for such a search, but will make no difference to the general level of queuing or time it takes to go through security.
That is the first reason for caution. The second is that the detectors may encourage security staff to check a greater proportion of passengers in this way. In other words, a larger number of people could be delayed a little more as opposed to a smaller number held up for longer.
When I put this to BAA, a spokeswoman declined to say anything - about the detectors, the proportion of passengers carrying liquids that are tested now, whether the proportion might increase, anything - but this is precisely what has happened following other innovations in airport-security technology.
A third reason for caution is that there is a danger of the detectors giving false readings. They will basically be used to identify hydrogen peroxide, which can be used in liquid explosive. It is also used in hair products.
This is not to suggest that anyone taking 100mls of shampoo through security could go the way of the Birmingham Six - the six Irishmen wrongly jailed in 1975 after traces of a substance on their hands were identified as plastic explosive. It was not until 1991 that the Court of Appeal concluded the traces had come from plastic-backed playing cards. Now that is a serious hold-up.
The point is the detectors may identify a lot of common substances as potentially dangerous and lead to further delays for passengers carrying them while they undergo additional tests.
Oh, and Manchester airport already uses the detectors. Incidentally, BAA insists it is confident of hitting its target of getting 95% of passengers through Heathrow security in five minutes or less this summer and 99% through in ten minutes or under. Remember you read it here.