In my experience, students tend to use ten times the amount of pressure and energy than required, so when I see talk of finger strengtheners I get worried. The great classical guitarist, David Russell, taught me an invaluable lesson in this regard. Put your left hand index finger on any note, say for example the fifth fret of the first string. Don't press it down yet, just touch it with the fingertip. Start continuously plucking the string. Obviously you get a muted note. Now slowly start adding pressure as you move the string towards the fingerboard. Soon the note will sound well. At that point, start decreasing the pressure back to where you started. You are teaching your muscles to apply the minimum pressure needed to fret a note. My bet it is that it is a LOT less pressure than you are used to applying. Now try it with other fingers. Then try playing a scale without open strings with this same technique. Go up and down the scale a few times from zero pressure to just enough and back again. Do this at the start of every practice session. Worked for me.
Your fingers are more than strong enough. Rob -- To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
