In other words: please go home and I'll call you.
'Head on home' is a real expression. Similar ones are 'head over there', 'head to ...', all of which just mean 'go to'.
'Head on home' is a real expression. Similar ones are 'head over there', 'head to ...', all of which just mean 'go to'.
Both people presumably do know what's really happening, and this is exactly why it's seen as unnecessary (and inconsiderate) to actually say it. There's no reason to call extra attention to something unpleasant.
"Hey, bud. Why don't you pick up those two plastic containers and follow me."
"OK, but dad, it really confuses me when you say that. Can't you just say 'please pick up those containers'? It sounds like you're giving me an option but you're really not."
Until he said that, I had never given it a thought. But he takes things very literally, so I can see how it's confusing even though he knows what I mean.
I think English littered with these suggestive polite negation statements.
As others have said, it's definitely a 'softening' of a request to make it more polite ('Go home' vs 'Would it be possible for you to go home?').
But I think there are some status games going on here, too. A subordinate would never use that phrasing with a superior.
While the phrase uses conditional language to 'soften' the request, it's also an imperative (an order) that's made to look like a request.
Try to imagine the boss saying this. How would they have said it - with an upward inflection at the end, as in a question like this one? Definitely not! The phrase would definitely end on a downward inflection, as in an order like 'Please go home'.
It's a curious turn of phrase that I'd suggest is particular to managers, parents, and other authority figures that need to maintain a veneer of respect for their subordinates. It also strikes me as uniquely American; I couldn't imagine a Brit or an Australian saying something like this (but happy to be corrected).
https://en.wikipedia.org/wiki/%C2%BFPor_qu%C3%A9_no_te_calla...
(I don't know whether it has exactly the same set of connotations in Spanish as in English, but it doesn't seem like the king expected Chavez to do something other than comply.)
I can't find the etymology beyond words meaning the body part or "primary"/"main". There's no direct equivalent in German for example despite the shared etymology for the other meanings.
I would guess that it is related to the body part in a figurative sense in the same was as "face" (i.e. turn your body in a specific direction) though I have no idea how "put your head there" would come to me "go there". I wonder if this was before or after "heading" became a thing for ships (which generally move in the direction they "face", so the "heading", i.e. how the "nose" is aligned, could go on to become a verb).
EDIT: I'm not sure it's pars pro toto because I'm not sure it directly refers to the "head" in the sense of the body part rather than the "heading" which is not directly related to the actual body part when talking about vehicles like ships.