Left-Hand Permutations – conclusion
As on any instrument, speed is important. The permutations, either in their simple form as finger patterns in one position or on one string, or in complex formations or lattices, should be sped up with a metronome. A first target would be a group of 4 at 100bpm.
A great way to build up strength in the hand is to practice permutations with slurs, in double, triple and quadruple groupings.
The difficulty of the permutations can be increased with the additional of sliding fingers (one or more per permutation) or by extensions (leaving one fret between one finger and the next).
Practice each permutation set with rest strokes and free strokes:
i and m
m and a
There are of course 9 permutations of the 3 R.H. fingers, so one can take this as far as one would wish!
The most important thing is to keep varying your routines and to keep pushing target speeds and endurance.