We have added an option in the Account Profile (https://runsignup.com/Profile) to help consolidate accounts. This is useful when the primary account owner (in the case below Bob Bickel) has entered a secondary user twice under different email addresses for two separate races (in this case my daughter Allison).
You can now do simple merges according to the directions right on the page:
This extends our other Account Claiming and Merging capabilities.