Minding the gap is most important at the Embankment station's Northern Line northbound platform. Due to the extreme curvature of the track at this station, the gap is perhaps eight to ten inches wide at certain points.

At most other stations where a "mind the gap" announcement is made, it's just part of a sequence -- "This train is the Northern Line, Charing Cross branch. This train terminates at High Barnet. Mind the gap." -- in an impersonal female voice, with (of course) a British accent. Well, Embankment is different. It seems that somebody decided the best way to get people's attention would be to change from a calm, British female voice to a LOUD, male, American voice repeating over and over again, "MIND THE GAP. MIND THE GAP. MIND THE GAP."

On the eleventh day of my trip to the UK, having gotten used to soft accents in most of England, hearing the harsh American tone of command made me jump a little.

Addendum: per a /msg from Gritchka, "The voice that says mind the gap at Embankment is not American but a very old-fashioned educated English accent, highly amusing to me too. The pronunciation "gyeap" now might sound American because Britons no longer say it."