Earlier quoted context omitted.
Given that you're not allowed to redeem tether for dollars I never quite understood why it mattered. edit: Note the difference between "trade" for dollars and "redeem" for dollars
The whales can redeem, in minimum chunks of $100,000. Mostly these are exchanges. Thus the peg is supported by the reserves in a roundabout way. If Tether can’t redeem, and trades break the peg, then ultimately either exchanges go insolves or anyone holding tether has to write off their holdings. Or both.
Also, I say "they can", but we have zero proof of this ever happening.