Just to clarify, I don't mean to dismiss the idea out-of-hand. I just think that there's a big difference between "statistically significant" and "genuinely useful".
Maybe 30 people would get out of an aircraft four seconds quicker....the question is, does that justify the cost to airlines?
IMHO the hypothesis hasn't even been proven. Only three or four evac trials were performed in each case...that's nowhere near enough to start drawing conclusions on statistical significance.
The other thing which the news report above doesn't mention is the number of trials which had to be aborted because the passengers were concerned over their own safety in the crush to get out.