A picture is worth a thousand words...
Proving 'poor workmanship' would be easier if the evidence is still at
hand, or has been documented with photos. Let the evidence (photos of poor
quality etc) decide.
For example, photographic comparisions of poorly done verses correct
'tuning pin height and coil setting and hammer installations' etc.
IMHO Go after the poor workmanship, and not the technician.
Dan
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