Swatches Lie!

I was just grumping at the PDX-Knit-Bloggers about lying swatches when the "why" clobbered me.

I started a navy blue Bohus cardigan last Wednesday at Knit Night, and commented that it was going to be my first adventure in steeking. Several gracious people offered support and, frankly, I figure I'll deal with it when I get there.

The cardi starts with cabled ribbing -- 3.5" of it -- so I was going on faith in my accurate swatch that I was getting gauge. Eventually (thanks to waiting four hours for new tires on Friday) I had enough above the ribbing to actually measure... and found that instead of getting 4" to 20 stitches, I'm only getting 3.5". This sweater is going to be way too small if I continue on.

And I suspect that the reason why is because I knit the swatch flat, and I'm knitting round. Sigh.

So, pictures for posterity before I rip this out and start over:
(I do like that ribbing!)

And the CPH that I should be seaming up? I actually started to do it today, but then realized that I'd better block the button bands while the body was still flat -- so that's where that project is:

(color not even close to accurate!)