Dave Wirth
The experience of playing guitar is different for each person who picks it up. There is no blanket advice out there that will withstand a thorough query as to what is best for one's own body. This is part of the reason I like playing and teaching guitar. There is always room for learning something more in my own playing, and it is a trip to help someone narrow down exactly what it feels like to play guitar in a way that works for them. Part of this work involves eliminating the wrong kind of tension and focusing on an easier way of playing.
The end goal of "good technique," in my opinion, is one in which the person playing guitar has only the right amount of tension needed to complete the task, and no more. Notice that I didn't say that the end goal was to be completely relaxed. The common, but possibly false, assumption is that we need to be 100% relaxed in order to play. My question for the folks who are after such a thing is: Is it really good to have no tension in your body at all? If that's the case, consider that without the right amount of tension, our fingers cannot possibly grip the strings. Without the right amount of tension, we'd be spaghetti on the floor. Without the right amount of tension, our hearts will not beat. Without the right amount of tension, we'd be dead.
Consider the following possibilities. First, many people figure out that playing guitar isn't very easy when their shoulder lifts upwards as they switch chords. Once eliminated, less energy goes into the shoulder, and more energy is conserved for harder chord progressions. A second example would be tension in area of the jaw/mouth. By learning to eliminate this tension, we could have more energy conserved and ready to be dispatched to play a difficult passage. I've noticed this in my own playing, and I have noticed this is a cross-genre technical issue!
The point is how to eliminate what is unnecessary, and conserve the energy for better pursuits, i.e. having fun. Guitar is not totally an out-of-body experience, but I have found that finding the best balance of tension in our bodies as we play is well worth the effort. Besides, I am pretty sure we are all looking to have more fun playing music anyway.
