On the following IRS page (https://www.irs.gov/publications/p544#en_US_2015_publink100072653), I just saw the following --- doesn't this confirm that my friend can claim the carryover loss exclusively?
"If you and your spouse once filed separate returns and are now filing a joint return, combine your separate capital loss carryovers. However, if you and your spouse once filed jointly and are now filing separately, any capital loss carryover from the joint return can be deducted only on the return of the spouse who actually had the loss."
