The question continually posed. The answer is simplle... the name comes from the title of a poem scripted by Noel Coward, a distinguished British playwright, director and thespian.

And for your cultural enhancement, we have scripted our namesake ditty below:

'Mad Dogs' and Englishmen (Noel Coward)

In tropical climes there are certain times of day.
When all the citizens retire, to tear their clothes off and perspire.
It's one of those rules that the biggest fools obey,
Because the sun is much too sultry and one must avoid its ultry-violet ray --
Papalaka-papalaka-papalaka-boo.
Digariga-digariga-digariga-doo.
The natives grieve when the white men leave their huts,
Because they're obviously, absolutely nuts -
Mad Dogs and Englishmen go out in the midday sun.
The Japanese don't care to,
the Chinese wouldn't dare to,
Hindus and Argentines sleep firmly from twelve to one,
But Englishmen detest a siesta,
In the Philippines there are lovely screens,
to protect you from the glare,
In the Malay states there are hats like plates,
which the Britishers won't wear,
At twelve noon the natives swoon,
and no further work is done -
But Mad Dogs and Englishmen go out in the midday sun...