What's the point???

I understand that if you drop the compression ratio within your cylinders you can run more boost therefore creating more horsepower. But I am running into a conceptual block here. If I drop the compression in my cylinders, but then crank up some more boost, aren't I ending up with the same pressure within the cylinder that I had before I dropped compression?!?

Nope, here's the deal, (this is a 100% volumetric efficency), a N/A engine pulls in air and compresses it (along with fuel) 10-11-12 (:1) times. When you run boost at 8:1, your commpressing the 6-12 psi 8 times. This would make it seem that you might as well run 3 psi on a cheap setup, but with boost and lower comppresion, the engine isn't working as hard as low boost and higher commpresion.

all the rage nowadays is running high compression and lower boost....

the lower compression is just there so that you have a larger window for tuning error

I'd personally rather have lower compression and be able to boost higher.:D