Both my bags were "caught" at check-in when they went on the scale...my bagpack with the laptop was around 10kg and my roller was about 25kg or so from memory. They allowed me to take both after some discussion and asking me to take some things out of rollerbag and put in my backpack - which made no sense to me, but once they put the carry-on tags on the bag, you're good to go at the gate.

Oddly enough, the same BR check-in staff working NH flights at TPE won't give carry-on bags a second glance, but when they work the BR flights, everything goes on the scale.