e.g. David Bobbett has an overall score of ~1050. His Volume is ~350. Therefore his "density" is approx 1050/(350/2.5) = around 8
So he has a high overall score, but is super-high in density - so likely much lower risk than the average guy who has a CAC score of around 20. See above on the "density" line - the guys with high CAC (Agatston) scores in right hand column have an average density of ~3.5 and their risk thus begins to sharply fall off, making them like Agatston=20 scorers. But David's density is around 8, not 3.5 - so he is way off to the right on the curve of falling risk (!)
It's a tricky one for sure, kind of a hyperbolic relationship with two vectors involved - overall score versus density quotient.
But it's all good. And yes, David's low Volume score is kinda remarkable, particularly how it plummeted from ~700 to ~350 while his Agatston gently increased from ~950 to ~1050.
AND NOW THE PLUMBING ANALOGY:
Explained it to my daughter who is going for medicine in college. Imagine buildings with corroding pipes:
1. Some buildings have small pockets of corrosion, but it is not really patched up much by the plumbers - they have lowish risk of flooding. (low CAC score, low volume score, low density peeps).
2. Then there are buildings with a lot of corrosion all over the system - but great plumbers have patched up all the weak areas (high CAC score, low volume score, high density peeps).
3. Then there are the shitty buildings - they have lots of corrosion all over, but crap plumbers who have not patched up very well (high CAC score, high volume, low density peeps). The latter need to get good plumbers in fast....or to go #LCHF asap !!!!
(p.s. the last guys (3) are generally poorly-controlled diabetics - corroding fast before their tattered systems can shore up the damage)