the LPC socket was sometimes showing the issue previously, refusing to
   find the LPC chip unless I reinserted it a number of times.

   But I did try to gently bend some leads to resolve connection issues,
   and thinking on that I guess that means I might have a way to consider
   whether I'm testing the chip leads or socket leads.

   Then later, I tested connections from the chip seating all the way to
   the teensy board, and found a number that were failing due to wear on
   the breadboard, and adjusted and squeezed these until they conducted.
   But it still wouldn't detect a known-working chip.
   I then removed it from the breadboard and wired it up hanging in the
   air with female jumper wires. This is not working either.

   It sounds like there are two issues: a failing socket, and failing wire
   connections. Not considering that there are likely two separate kinds
   of issues could have worsened the confusing frustration.

   I'd like to compare the electrical activity at the chip pins to what
   the device is supposed to send somehow.

   Maybe I could try to add debug information to flashrom's serprog
   protocol, although I'm feeling that might be inefficient.

   It's important to eventually have logic debugging. But maybe something
   more reusable than serprog additions.
   Thinking about testing manually vs building or finding logic probing
   tools, one thinks about time. Both tasks are slowed from human issues.
   I bet there's existing code to use raspberry pi as a logic analyser
   somewhere ... but I'm unsure if the frequency will be sufficient
   without learning the flashing protocol. Learning the protocol would
   normally be expected for hobbying this.
   Thinking on manually testing things with more rigor. Ensuring the chip
   used works. Considering every pin in all the ways, and verifying they
   all work before a test.
   It's frightening to think of putting all that work in and having it
   still possibly fail for unknown reason, but it may be an important and
   rational diagnostic step. One that has not yet been done.