Quick Breads: Mixing the Batter
As a general rule, I add the dry to the wet, i.e., the wet would be in the mixer and the dry would measured out in a separate bowl and added after the wet is well combined, but it's not always the situation. As you'll see in the link below for making scones, breads like bisquits, scones and even piecrust require cutting the fat (butter, shortening) into the flour first, then adding the wet ingredients.
Here's a link with some explanation:
and another, a bit hard to read:
and for something completely different, a wet to dry technique for making scones:
And one for especially for more info than you ever wanted for quickbreads:
Does it make a difference? Yes, check the links and you'll get an idea about constructing batters, adding eggs, flavorings, leavening, in which order and what all these things do in batter, etc. for optimum results. Here's a Chow book link which I highly recommend, it'll make you a pro: