Wonderfully put! You did a great job of boiled that down to a short statement.
After your explanation and a link to HowStuffWorks.com I feel I understand how the synchronizers works!
http://auto.howstuffworks.com/transmission3.htm
I can also see how a poorly done Double clutch, could cause extra wear. I see the possible issue like this, let me know if this is close to what your thinking.
The frictional portion of the synchronizer is not meant to handle a lot of force. It could be over powered causing the soft brass teeth to encounter too much force, and causing excessive wear.