Why run dual quads?

that question has been asked many times, on a factory dual four versus singe four is worth .four tenths faster. chev had dual fours on 56 , 265 and the 283, mopar had them on 318 poly, 354 hemi, 392 hemi, the 62 413 and 383 , ford had them on 427 FE. i know this, when you punch open dual fours, has way more response. i had them on my old 265 chev, planning on putting them on my 273 later this year. all these setups had progressive linkages. fuel milage was bout the same , till you stepped on it. just food for thought.