I just went into the test database I use and deleted all the rows in the wp-option table that began with 'bfa'. This included all the rows created pre 43.4.7 and the bfa4 record. This is equivalent to doing a fresh wordpress install and activating the theme for the first time.
I made some changes
I then pressed the 'Reset ALL theme options' and while I did not check each and every option, the ones I did check were reset to the defaults.
If you had a release prior to 3.4.7 you could still have the old bfa records in the wp-option table. to check, in phpMyAdmin, issue the following
SELECT option_name, option_value FROM `wp_options` WHERE option_name REGEXP '^bfa_ata_';
make sure to change the prefix to match the one you have.
If you get any hits, you can delete the resultant set.
Please make sure to do a database backup BEFORE you do this.