Must be O/S dependent of course.
Example:
Ability to swap in 4L80E Transmission & Transmission Diagnostic segments in place of 4L60E segments for guys that have smoked their 4L60E too many times.
Or swap in 6 liter code in place of 4.8 liter code.
I can do it in binary but it's slow, tedious, and error prone. Got gray hairs to prove it (oops, those are caused by my kids... )
EC