My only comment would be 9/11 didn't send SFT bust, the school was in financial trouble well before 9/11. Remember there were plenty of students at SFT training and plenty of students signing up for courses up to the time it went bust. Although SFT went under soon after 9/11, it was too soon after 9/11 for the affect of 9/11 to have affected trade. Do seem to remember it didn't take the management team/ a certain director from SFT to resume operating a training school just over road form the SFT not so along after (what is now EPTA).
Four Forces, "financial management" or "intentional mismanagement" as the case was by the Iverson brothers may have more to do with downfall of Four Forces than 9/11.