No, I guess I don't agree. First off, watching full-screen 16:9 content such as sports, TV shows etc.puts more of a demand on the ABL. When they switched, just briefly, to Directv during the shootout, I could see the ABL kick in big time on the Panasonics. Yet the 8500 held the brightness far better. When I owned my Pro 151, I saw the ABL effect far more often on full screen shows (sports, movies, etc.) than many letter boxed movies. But as recently as a couple of weeks ago, I was at a MHT comparing the VT to the 8500 and even with a letter boxed movie, there was a bright overcast scene in which the overcast sky occupied perhaps 40% or so of the screen. On the VT the overcast sky dimmed noticeably while the 8500 exhibited no dimming at all.
So yes, I firmly believe the ABL plays a pretty significant role in plasma viewing.