To me, asking a pilot "are you happy to continue" means you're not.........why would that be?
I agree with you on that Jerricho.
Not sure how "official" the policy is at Heathrow, but from this:
http://wwwe.onecert.fr/projets/WakeN...ul_Johnson.pdf comes this:
"•Wake Vortex Separation applied to 4DME from
touchdown.
•When the lead aircraft is inside 4DME and a reduction
of ½ mile or more in the required wake vortex separation
occurs, the pilot of the following aircraft must be
informed."
... meaning no need to say or do anything down to 1/2 mile below the standard?
Not saying I agree with it, just seems there's some fairly liberal interpretations of Doc 4444 out there.
Also seems to me the last 4NM is when you DO need it, as the chance of a recovery from a major upset at low altitude/low control effectiveness is fairly unlikely.