Extra line-broadening vs. projected rotational velocities for the stars from our OB sample (open circles) and the sample studied by Lefever et al. (2010, filled dots). Stars assumed to be affected by projection are highlighted by asterisks. The large diamond indicates the magnetic star HD 93843. The solid and dashed lines represent the one-to-one correspondence and the 110 km s^-1 limit of Θ_RT, respectively.