The healing brush is kind of similar to what I used to use when I needed to touch up. I click on it, then put my mouse over the area I want to "copy" then while holding the Alt key, I click. That picks up the colors from that area. Part of a "problem" I have with the healing brush is that it is more work to flip back and forth with sizes if I am doing smaller areas. You can adjust the size of the area you take from and brush over just as you do with the paint brush. Sometimes it is easier to paint over instead of using the healing tool... especially around the eyes.
But if you are doing a pretty noticable single blemish, it would be far easier to use.
I'm sure that didn't totally make sense, but the healing brush will just take small areas of what you are trying to correct and it will take all the colors around and just "copy" it to the new location when you click. Sometimes the variance in colors makes it too hard to use in smaller or different shaded areas.
I use both equally though.