IR reasoning for Chain/Pulling:
Chain System has been introduced for the betterment of traveler, to utilize in case of: Traveler dropped from moving train, Fire in Train & other casualty. For the benefit of all, Chain option cant be scrapped from any train, even if its been used for chain pulling.
#Most Chain do have the message: Chain pulled without genuine reason will lead to fine/imprisonment/both.
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#We demand scrapping something, which is genuine benefit for traveler, instead of self-check. Train getting chain pulled is quite visible @ Big Junction.
TTE/Guard Accessibility: In case someone dropped or any coach catches fire, till TTE get informed, it will already be much late!