93 miles of driving after the stiction fix, it could once again no longer go in a straight line. The next step would be sending more diagnostics to the GUI, in realtime. It may not be seeing the deviation in heading required for it to kick the integral or it may be waiting for a deviation in the wrong direction. After drifting right for a while, it suddenly kicks left. Showing the realtime deviation in heading, what deviation it's waiting for, & the feedback is part of the solution.
Other ideas were adding noise to the feedback, because it seems to knock itself straight when it hits bumps.
The raspberry pi zero W was too good to be true. After integrating 10 of them without any issues, packed one in a static bag & commuted with it. It no longer detected wlan0.
dmesg|grep brcm went from showing
[ 35.073582] brcmfmac: F1 signature read @0x18000000=0x1541a9a6
[ 35.103366] usbcore: registered new interface driver brcmfmac
[ 35.519555] brcmfmac: Firmware version = wl0: Aug 7 2017 00:46:29 version 78
[ 35.520794] brcmfmac: brcmf_c_preinit_dcmds: CLM version = API: 12.2 Data: 7
[ 42.937355] brcmfmac: power management disabled
to
[ 35.693070] brcmfmac: F1 signature read @0x18000000=0x41e041e
[ 35.693567] brcmfmac: brcmf_chip_recognition: SB chip is not supported
[ 35.693580] brcmfmac: brcmf_sdio_probe_attach: brcmf_chip_attach failed!
[ 35.693592]
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