OK! Curved needles do work for sock yarn, I just had to drop down to 1.5 mm pricks, and it gives me about 10spi. The yarn band says 7.5 spi for Amrican size 2 needles. I like the firmer, 10 spi fabric better. In fact, the firmer fabric is much more like the fabric in those nice Smart Wool socks that my wife just bought. (Those Smart Wool sock are knit at ~32 spi so I am not even getting close to their gauge.)
This swatch was started on 2.38 mm pricks, and I just could not make those big needles work with the fingerling yarn. You can see the big stitches at the bottom. Besides, I do not like the fabric.
The wood thing is the knitting stick I am using.