kmurdick wrote:The ability to read well is much more important than being able to read at sight. In addition, the better reader you are, the better sight reader you will be. Here is what I mean by good reading. Choose a piece of music that is beneath your current level. Take a portion of the piece - perhaps just one line - visualize playing the portion in your mind without using the guitar. Then see if you can play this portion on the guitar slowly without error the first time you play it. If not, repeat the process. If you can't get it at some tempo after two or three tries, it means you are using material that is too difficult. Remember, you can already sight read music at some level. The purpose of practicing good reading techniques is to push this level up.
The reason I do not like the idea of just practicing reading at sight is that you end up practicing errors. Visualization allows you to look ahead and play the notes accurately.
This is more or less how accomplished musicians sight-read, by my understanding--commonly a measure or two ahead, or if the passage is not busy even further. Before playing at all, they have scanned for key, modalities, potentially tough or easy spots, and for idiomatic and generic features.
I agree that for either purpose, the accumulation of conscientious reading experience is an essential driver of progress. Your approach is certainly valid (and part of a proper approach to learning a piece, too), but so is the sight-reading approach outlined previously in this thread. They each emphasize different reading skills. Different students at different stages may benefit more from one than the other, but it's good practice at every level to do both.
JohnB's point is well taken. One reason classical guitarists are notoriously poor readers is that most of us do far less ensemble work--if any--than players of other instruments. Ensemble playing develops not only reading but listening skills--two skill sets that overlap and reinforce each other.
I'm sure this is what you meant, kmurdick, but it needs to be said that the approach you describe should involve audiation as well as visualization.