Student Question - Read only if in magnanamous mood.

[Benjamin Treuhaft]

Hi, John.
     You don't have to leave a groove, just a hint of where the lines
used to be so  as to be sure you didn't take any felt off below where
the grooves were, in other words you ldidn't steal any life off the
hammer - the player should do that job.  Always space the hammers if
they are out of line, and of course if you have to move a string or two
knock yourself out.  The hammer should be absolutely parallel to the
strings at the crown, keep checking for that as you go. The hammer
looks, ideally, like the pointy end of an egg when you're done shaping
it.  This keeps the striking point accurate and voicing lasts longer.
Benjamin Lettuce Treuhaft
Berkeley, Calif. (Senda Piana to Havana)