The general rule in Photography is ‘KISS’, keep it simple stupid. Often though in the studio it can be easier to introduce another flash head then to not.
The shot above looks deceptively simple but in fact uses a total of seven flash heads!
The key to this sort of thing is to build slowly, start with one light and work with that, then introduce another and continue to experiment and build.
This shot has one main light using a large Elinchrom Rotalux soft box, then a fill light on the other side. A flash over the top of the model with a small soft-box to act as a hair light; and finally for the background, two flash heads on each side fitted with barn doors to light the back ground. Yes it sounds over kill but when your in a well equipped studio and have plenty of time you might as well experiment and learn.