I was just looking at the specs and manual (found via google search at
http://www.ifirobotics.com/victor-88...r-robots.shtml and
http://www.ifirobotics.com/docs/ifi-...al-9-25-06.pdf)
The spec sheet states that the dead band is centered around 127. The manual describes the calibration process.
I would expect the defaults in the code to match the specs, not some empirical test (with out a lot of explanation as to why the specs are wrong and must be overridden by default).