Steve,
We share the same confusion. Maybe I can open this up further. Isn't the wattage/amperage of a pixel based on it's max rating on white? So on dumb stuff when split to 3 discrete channels the load is distributed right? (My pretend EE knowledge) IE 200 dumb pixels is 60w TOTAL (when white), 20w red, 20w blue, 20w green, a total of 60w white. Also for the strips assuming the wattage is correct, 72W/3 = 24w = 2A @ 12v. There is probably a better way to explain this...
I say Steve's OK but I am a newbie to dumb gear.
Starting to educate myself now as I plan to add dumb elements next year.