On the point of standard weights, I have heard that audits conducted found them to be acceptable with no real issues. The main thing that has changed in the last 20 years is the charge for baggage issues, so that now everybody is trying to cram as much into overhead bins as they can. Carry on baggage is generally only accounted for an average of 5 kg per passenger. Its quite obvious that is now the minimum people are carting. I've never seen so many flights where cabin bags have to be put in the hold due to absolutely no more space in the cabin, esp on 737s.