Dr. Scaifani came up with his analogy in good faith attempt to explain a complex topic in simple terms to a layperson. It wasn't meant to be the definitive statement on the scientific underpinnings of CCSVI.
The problem is that the brain is not like a barrel and therefore the analogy breaks down quickly.
To me the brain is more like an engine than it is a barrel - specifically, a forced induction (FI or turbo) internal combustion engine. Petrol (blood) is mixed with oxygen and delivered under pressure to the engine (brain) where it is burnt, converted to energy, and then the spent fuel is expelled through the exhaust piping (veins).
As with all FI engines volumetric efficiency can be increased by removing restrictions in the exhaust. The best results can be achieved when the the exhaust port is slightly narrower (to increase velocity) and the widened downstream. The goal is to reduce back pressure as much as possible. If there is a restriction downstream, back pressure will increase and VE will go down.
But here is thing, the intake pressure (boost) will remain the same with or
without the restriction. This is why arterial pressure will not go up just
because there is a stricture in the exhaust pipes draining the brain. But VE will go down and the brain will not get as much as the good stuff that it needs.
Just as car enthusiasts like to increase the HP (but not the noise and
pollution) of their FI engines by removing the catalytic converters and using high flow mufflers, brain efficiency should be increased by removing restrictions in the venous downpipes.
This would explain why persons with CCSVI often feel fatigue and brain fog
- their brains are not getting as much oxygen as it should.
Where the analogy breaks down however is with reflux - unless one could
say that spent fuel is not being evacuated is refluxing back due to back pressure and damaging the wiring. But that doesn't stand up well
But it can explain why many people who have had their blockages cleared
experience abatement of brain fog and fatigue.
[edit: I meant this as a reply to the CCSVI theory makes sense to me thread, but due to mental error started a new thread. This is a pre-liberation treatment mistake