Don't kid yourself. Brian wrote that self-serving piece to be the anti-PADI hero at DEMA in attempt to gain market share. Read the letter again, Brian essentially says leave PADI and come to TDI/SDI because we'll support you no matter what happens. We can comfortably assume Brian did not have all the facts in the case and was under or perhaps misinformed at the time he mounted the soap box, but... Nothing will deny the fact that he knew [at the time of publishing] his insurance underwriter has a severability clause for accidents resultant of a standards violation. His liability insurer would NOT have covered this instructor and he knew it.
The only way Brian can make the claim is if TDI/SDI intends to write the check for future judgments incurred by an instructor in cases when the insurance is insufficient, or the insurance severs per the clause(s) in professional liability indemnity contract. Count me as VERY dubious that TDI/SDI has the balance sheet to self-insure.
