I am a production potter so a lot of the small items that I make get made in bunches. I have a work area where I can lay out several spoon rests, or Christmas ornaments or small sets and do them all at the same time.
I don't tend to work on multiple original paintings at the same time. I do best when I zero in on one and bulldog it until it is done. Although some paintings need to have a "time out" and sit in the corner until I'm ready to deal with them again. And while they rest, I can work on something else.