The "we owe it to ourselves" theory strikes again

FRED Blog, 9 December 2019:

The federal debt reached 103% of GDP in second quarter 2019. These numbers, however, don’t properly reflect the amount owed by the federal government to private bondholders, since certain federal agencies (primarily, the Social Security trust funds) also hold federal debt. These agency bond holdings are liabilities the federal government owes to itself and therefore should be netted out.

The premise -- that the numbers don't "properly" reflect the amount owed by the federal government to private bondholders -- assumes the conclusion.