I didn't bother to read all these pages, but half my work was done with a Rollei 2.8 TLR, much of it handheld. Faster film and monopods are helpful. See some of my work at http://www.frankpetronio.com
Last year I stopped shooting 6x6 because I was getting stagnant - composition is almost too easy with a square, and I was tending to do too many centered and symetrical images. Also, I began to feel that I was compromising with medioum format, and that for times I wanted to capture information and detail, I should be using 4x5. For interiors and fast shooting, I use a 35mm or digital SLR. They seem better suited to those tasks - the Rollei was always inbetween.
But I will probably come back again. I just have to switch gear occassionally.