bealine: UK/Ireland Domestic to UK/Ireland Domestic should also be screened, but pax who know where they are heading may circumvent this by remaining in the Domestic gate area instead of following the transfer route.
Pax who know what they're doing can also circumvent this
very easily in one of the higher-risk terminals at LHR, which is (I suspect) why BA has additional gate screening for the destination which it operates from there.