Well, imagine apple puts all information necessary to build an iPhone into a patent. Then Samsung builds a phone identical to the iPhone, except it's green. If the patent specifically mentioned black, gold, but not green, then a green phone might not infringe.
My point is that too specific can also be a drawback.
Too specific is only a drawback to the patent holder. And a single-patent iPhone patent would cost a fortune to file anyway. Having overly specific patents is not remotely a drawback to the rest of us.
I'm more in the "everything is a remix" camp, at least as far as software and design patents are concerned. If Apple didn't create the iPhone, someone else would have made something similar.