Auto Dual Extruder Offset Calculation

Has anyone found a way to automatically calculate the dual extruder offset. Off the top of my head it would consist of a pressure sensitive plate that reads where both hot ends touch it and automatically spit out the dual extruder offset values. Anyone done this / working on this? Bueller, Bueller, anyone???

Not dual extruder, but related:

I think it would be possible to do what you have described using a similar method.