Re: No quite wizadry but.../ Percussive Maintenance @TheNeonSpirit
"The condition was termed 'Stiction'"
It wasn't just IBM with this problem. During the early-mid 1990s it occured on a variety of drives from a variety of manufacturers.
The alternative to a tap - if you could remove the drive - was to twist it sharply around the platter spin axis and put it back in quickly. This usually worked without risking head damage.