Is it really that hard to understand the difference between a valve extender and a valve stem for disc wheels? Ive seen so many people using these terms interchangeably, and its really frustrating. Can someone please explain, in simple terms, what the actual difference is? Is it just a matter of length, or is there a functional difference? And dont even get me started on the so-called experts who claim that valve extenders are only for deep-section rims. What about the guys running 28mm tires on their disc wheels - do they need extenders or not? And whats the deal with the length of the valve stem itself - is there a standard, or is it just a free-for-all? Im amazed that in this day and age, theres still so much confusion around something as basic as tire valves. So, come on, wheel-building wizards, enlighten me - whats the real story here?