BA writing on their website say that due to "new security procedures" check in at Heathrow is now 2 hours :-
BAA Heathrow has introduced new security procedures following a recent security review. These are leading to delays through central security for customers of all airlines operating from London Heathrow Airport. With the start of school half term, we are expecting the airport to be busier than normal.
BAA Heathrow assures us that it is doing all it can to minimise the effect on our customers and I can assure you that we are also doing everything we can to make sure all our customers get away on their flights as quickly as possible.
Customers booked to travel should arrive at the airport two hours before the scheduled departure time, as normal. However, we advise customers to minimise the amount of hand baggage they carry with them and allow sufficient time to clear central security searches
Meanwhile London City airport (also operating BA flights) are able to carry on with 10 minute checkin :
(c) Ten Minute Check-in
In response to a question by David Kent, Charles Buchanan said that in spite of the growth in the number of passengers the Airport still offered passenger check-in 10 minutes before departure. It was likely that most passengers aimed to check-in 30 minutes before departure but in doing so they felt secure in the knowledge that if there were travel or other delays they would still be accepted 10 minutes before the flight departed
http://www.lcacc.org/committee/jan06mins.pdf
What I want to know is this. How can London City perform all the required checks within 10 minutes that take BAA at Heathrow 2 hours ? The difference in walking time onward from security to the gate is not 1 hours 50 minutes, as we all know. What on earth is Heathrow doing that requires 2 hours ? As we all know, this is in reality 2 minutes to negotiate the security check, in exactly the same manner as the very professional check always done at London City, and 1 hour 58 minutes messing about