It is true that in emergency situations in real life, crisis management becomes difficult and becomes uncontrollable even after deploying all resources at the command. For eg. when riots take place people are asked to stay in doors and curfew is imposed.
Exactly such situations also may happen even in stock markets despite ever vigilant SEBI and stock exchanges.
When panic engulfs valuations do not count.
It is better to prescribe lower circuits for all scrips under such cirmustances [say 10%] rather than imposing additional margins.
As the SEBI and exchanges are more informed and well versed they can take appropriate decisions to deal with such difficult situations.
However I want to bring to the kind attention of authorities that small investors are denied to buy the stock on fall, whatever may be the technical reasons, and they have lost the opportunity to recoup their losses, because they are not allowed to purchase.
I request the authorities to look into it and protect the interest of small investors.