I'll let
@Steve respond for himself, but I wouldn't be surprised if he isn't staying strictly within the carry-on weight limits at all times, but that he may have a way to scale down when necessary (or pay for excess weight).
Most of us have a Plan B for being able to distribute our load around if we get challenged on weight restriction limits. My Plan B consists of a deep pocketed photographer's vest (or winter parka), along with the ability to move lenses and/or bodies into my personal item bag. An optional Plan C might be to use a camera bag with a removable ICU, and be ready to remove it and take it as carry-on (while still distributing gear as necessary), and let the airline gate check the nearly empty camera backpack.
I have rarely been challenged on the weight limitations when I travel, but I predominantly travel on US carriers. However, smaller "safari aircraft" are a different situation.
I have been challenged on both Air NZ and Iceland Air when traveling internationally. I was recently screened on an Iceland Air flight to Reykjavík, when I was traveling with my Pelican 1535Air case with a Z9, Z8, three f/2.8 lenses and a 20mm 1.8 inside (and more), which was nowhere near within the weight restrictions. I flew on Alaska on the initial leg of my trip, and the Pelican case was not an issue. But things were different when I had to connect to the Iceland Air flight.
I seldom fly with my Pelican case as a carry-on, and if I had thought more about having to change carriers mid-route for this trip, I would have brought one of my camera bags with removable ICU instead of the Pelican case. Anyway, I quickly started working on my Plan B options, and I was able to distribute the load sufficiently to pass through the screening process for the Iceland Air flight(s). Going forward I will pay more attention to my itinerary details (and probably won't try to take my Pelican case on non-US carriers).