Indy/rhs heads?

What's referred to as "under the curve" is the actual movement of air past the valve from the moment any particular lobe begins to lift it, to the time it closes. it's like a graph of a horse power or torque result. We call it the pwer curve for that reason, and the power produced under the peak line is the whole "area under the curve". So when BJR talks about flow "under the curve", he's not talking the max lift numbers you're reading... but rather the total flow from beginning to end as one lump. An example... You have a 5 gallon bucket. You're going to fill it exactly to the 5 gal capacity thru a 5" diameter pipe that is closed off with a cone shaped plug. If you push out the plug 1" and then turn on the water, it will take 2 minutes to fill the bucket. If you push the plug out 5" so the pipe can flow it's maximum and then turn on the water, it will take 10 seconds. So you have two flow rates, and one final volume filled in that time. Well, now lets say the water is already turned on when you start to push out the plug and you go from sealed to wide open to sealed in order to fill it. Let's say it takes 25 seconds worth of pushing open to full and then closing. Why? The 5 gallons can be flowed in 10 seconds.. right? So how did the time to fill go down so much? Because very little of the flowing was done JUST at the maqx flow rate. MOST of it is done while the plug is moving. The "area under the curve" is the total amount of flow once the plug is no longer sealing to when it seals again.
Same is true with an engine's valve motion.
I think where you will get the variations in opinions... And really, they are ALL just opinions until the engine is running... Is the importance of the flow at each step along the opening and closing ramps. BJR likes small ports that flow fast at low and reeally come on hard at mid lifts. If you ask others, they will tell you that this is the formula for huge torque when the driveline is matched. As for my own opinion, I'm in the middle. I like to keep the volumes down to a point, but I'll simply match everything and let the chips fall where they may. Any decent builder can predict with decent accuracy what the particluar package will do with each change. The physics never change. Only the opinions and choices made as people push envelopes and figure out more of it.