Sh*t, I've been doing it wrong these past twenty years.
Maybe. Often the pulse sequencing to be supplied to servos is refered to as PPM (pulse position modulation?). It is a somewhat specific timing control format for the control chips contained in servos. Generic PWM control can have a control pin anywhere from high all the time to low all the time, and the pulse cycle can be from low frequencies to very high frequencies, which would have to be carefully developed to control a servo. The main issue in the forums is that persons often assume that generic PWM code that controls a simple DC motor will also work to control a servo. The servo library develops the specific pulse timing required for use with the control chips in the servo. The chip in the servo then develops the typical PWM to control the H-bridge/motot in the servo. The below link has good info.