For the most part, I am happy with my overall finger plucking technique. I'm a floating thumb player that does well with moving quickly from string to string and I'm great with muting. However, I have been trying for years to increase the tempo that my middle and index fingers can "walk", but without much success. I am constantly pushing the two fingers to increase their playing speed, but I cannot seem to get them to move faster. Any ideas on exercises or techniques that I can try to get more plucking speed out of my right hand?