> Obviously you cannot have just five faces "solved", but it is also not possible to have just four faces "solved".
Not true. There are many examples, but here are a couple examples sequences that leave only two faces scrambled:
1) F2 R2 F2 R2 F2 R2
2) R2 U' F2 R2 F2 U2 R2 F2 R2 U' R2
> The easiest way to split a cube apart is to rotate one side by 45 degrees, and push the protruding corner piece until its latch pops out.
That's a pretty rough way to do it. You're better off turning the top face by 45 degrees and using a scredriver (or your finger) to pry one of the edge pieces upward until it pops out. The rest of the pieces will come out pretty easily after that.