From 1978 through 1991 there were 18 evacuations of large, Canadian-registered, passenger-carrying aircraft. In addition, there were 3 evacuations in Canada of foreign aircraft. These 21 occurrences involved 2,305 passengers and 139 crew members and resulted in 91 fatalities and 78 serious injuries. Some 36 fatalities and 8 serious injuries occurred during the evacuation process.
I posted that as information that some might find useful during this discussion.
I recently read a report of an RTO of a 737 flown by an Irish operator, condensation from the aircon occurred at the same time as a strange smell when take-off thrust was set, the aircraft was evacuated based on both visual and olfactory cues and one passenger broke her pelvis and her neck. There were other injuries as well. Nothing was found to be wrong with the aircraft.
Just food for thought. I think I would have evacuated the aircraft in the Singapore case but it is definitely a topic worthy of robust debate.
Sunfish's advice to follow your SOP's is often not helpful as the SOP's can't cover all the variables and are rarely black and white in their advice.