>What the H does "you really screwed the pooch that time" even mean?
"…dictionaries of American slang recognize that “screw the pooch” must have developed as a euphemism for an older military vulgarism: “fuck the dog.”
In The F-Word, lexicographer Jesse Sheidlower gives examples of “fuck the dog” dating back to 1935, when it appeared in Jack Conroy’s novel A World to Win. And there are even a couple of examples from the World War I era that refer to the expression obliquely, in the more decorous, and therefore more printable, versions “feed the dog” and “walk the dog.”
Whether the action was feeding, walking, or fornicating, though, all of these early examples were used to mean “to loaf around” or “to waste time” (dogs have often been associated with laziness, as in the expression “dogging it”). Later on, possibly around World War II, “fucking the dog” and its euphemistic equivalents took on a secondary meaning of “blundering.”
But where did the enjoyably assonant “screw the pooch” come from and how did the Mercury astronauts end up using it? Searching for clues, I noticed that the entry for the expression on Wiktionary had been anonymously edited a few years ago to give credit to “a Yale graduate named John Rawlings who helped design the astronauts’ space suits.” In turn, the Wiktionary editor claimed, Rawlings got it from a Yale friend, “the radio DJ Jack May (a.k.a. ‘Candied Yam Jackson’),” who had softened “fuck the dog” to be “simultaneously less vulgar and more pleasing to the ear.”"
https://slate.com/human-interest/2014/01/screw-the-pooch-etymology-of-the-idiom-dates-back-to-nasa-and-the-military.html