Patrick Handscombe may be on to something.  We've all probably seen
a roll, often a jumbo roll, come to a stop as a big, powerful chord
plays.  After a little heart flutter, I've noticed the take-up spool
still turning and the roll winding a little snugger.

The problem?  A lot of friction at the tracker bar.  Perhaps the slot
was Ampico's idea to relieve that issue.  Sounds like something they
might do in the B system.

By the way, I've seen extra holes in the tracker bar that were exposed
to suction only in rewind, just so the roll had some drag as it rewound.

Jeff Davis - in now sunny Seattle