I do not have two examples, maybe the old Ferrum Aeternum tab (which has recently been updated) and the old one are examples of small improvements. Currently I let my algorithm optimize a cost function (where the cost function currently calculates the amount of shifts needed to accomplish the suggested hand positions). Because minimizing shifting is not always better (ie I think that running my current algorithm on the intro of Thunderstruck by AC/DC, which is played on a single string, will generate some quite unplayable tabs), I have to adapt this cost function. At some point, however, this will come up to personal preferences. I am therefore thinking of including a 'Mother of all Cost functions', which consists of the weighted sum of some cost functions. My idea for the genetic algorithm was to let one gene determine part of the structure of a neural network, and a different gene the weights. You have a point about the guitar technique part, I have been playing guitar for some time, but only picked up electric guitar when the first Rocksmith game came out. I'd consider myself to be of intermediate level, I am able to score 90%+ on almost all songs I play, and the only technique I encounter which I don't know how to perform is sweep picking. I am not very knowledgable on music theory.