If one eliminates the act of selling and taking a tax loss, either by choice or because the shares are held in a tax-deferred account, the decision becomes simple. One either holds or adds to the position at these near zero levels. Like tourney poker, we are short stack and either play conservatively until given the opportunity (cards), or say the heck with it and get aggressive now whatever the hand.
Barring TDC shutting down, an outcome I strongly doubt, my gut says adding is a leveraged bet on lowering cost basis and recovering going forward. Guts and glory or foolish folly? I'll bet even some of TDC's most serious detractors are tempted.
DYODD.