For those who haven't seen Homicide, David Simon got his "masters" in television through that experience and ultimately led to, what most of us perceive as, the genius that was the Wire. Perhaps most importantly, he learned that he needed to control the entire process if he wanted to see his creative vision played out to the fullest--which is what we got with the Wire. He was only an adviser on Homicide, and accordingly, the show went to **** after the showrunners ran out of stories from his book of the same name and allowed it to devolve into a typical crime drama. Many of the true anecdotes from the book evolved into those used in a refined version in the Wire.
So Homicide was a precursor to the Wire for sure, as was the Corner, but I too don't understand how that takes away from the Wire's greatness or how that fact is relevant to this discussion. This is coming from someone who read both of Simon's books and finished the Wire in realtime (though I didn't start watching until Season 4 was running), but I can't be a hipster...I mean, I look awful in skinny jeans... sooooooo