It’s the 5th explanation provided. I could belive it to be the case based on when I first began to hear this term. Larry Holmes became the heavyweight champion in 1978 IIRC. But at that time I would have only been hearing a limited amount of street slang in Philadelphia. Any earlier use would quickly dispel that notion. I find the concept that it refers to the great detective kind of strange. The name Sherlock is very uncommon (I don’t know if any real person ever had it). If you want to refer to the detective, the name Sherlock will get you there without misunderstanding. It is also part of another common phrase, “No shit Sherlock”.
But I got no idea what the truth is. You tell me Holmes.
Well, I’ll be! I just wikied it and it’s a much older term than I thought. Refers to 19th century migration and is short for home boy. As in the boys back home.
I figured it was for home boy, but didn’t know the tie with moving approx. north.
No, that would only make sense if it was short for a longer word that began with “ho” and ended with “mes.” (I can’t think of any word that this would be.)