Nothing new to see here. They were doing it over the English Channel and North Sea from 1942 onwards on a regular basis. Zero feet, best fast cruising speed, looking out for shipping ahead (didn't matter if they were friend or foe they would both shoot at you if approached fast and at low level), keeping an eye open for sea birds directly in your path or enemy fighters above, and waiting to hear the first signs in your radio headset of another member of your flight giving a warning call of peril or the enemy coast ahead.
The screen shot is from the 1944 British movie "For Those In Peril" which is about the RAF ASR High Speed Launches and shows RAF Mustang Mk.Is playing the role of attacking Me-109s, at low level.
ThoseinPeril by
Colin Ford, on Flickr
And all done with armour, armament and close to a full fuel load.