If you are a future (or current) pharmacist, you need to know warfarin. You don't need me to tell you that. Every teacher and preceptor you've had since you started school has been drilling that into your head.
However you've probably also noticed that few will actually tell you how to dose warfarin. Sure, you learn about purple toes and birth defects, but that doesn't tell you what to do when your patient's INR is 5.6.