I've mentioned often in the past that I use small running stitches over a design marked up on the back of a piece to transfer it to the front. This sounds like - and is - a lot of work: I have to mark the design onto the back somehow (an iron-on transfer on lining fabric, usually, but it could be traced, prick and pounced, etc), and then have the effort of stitching over it with stitches that are not intended to be seen as part of the finished item. Why do I bother, when it would be quicker and easier to mark up the front in the first place?
This is why.
Here's a part of the design with the running stitches marking out the design:
The lines are rather wobbly as the running stitches are going through several layers of fabric (the linen lining, the cotton sateen background, the Vilene lining of the appliqué section and the silk of the appliqué itself) and it's hard to keep them as straight on the front as they are on the back, especially with a design this complex, but I'm more interested in the shape of the spiral. It looks wrong - the part over the central circle is too high.
So, when I added the couched thread, I ignored that bit of the transferred design and put it where I felt it ought to go instead:
That leaves the stitches of the original line (and the wobbly ones) on show, but a quick bit of unpicking later and voilà!
They're gone, and you'd never know they'd been there.
If the design was marked on with pen or some other more or less permanent medium, I couldn't change my mind, or not easily. This way, I can make changes as I go, plus I don't have to worry about lines showing through, or ink spreading and making a mess of the fabric.
So yes, it takes more time and effort, but it saves a lot of heartache. I can recommend it.