Yes, that's a well-established trick for icy roads. It does work.

As hinted at in the OP, there are some safety limits to observe. Tires that have been partially deflated are only safe for low speed operation. At high speeds, they are distinctly hazardous -- poor handling and possible blowout (loss of bead seal) under the stress of emergency steering/braking.

But it's still a good trick to have up your sleeve. It's pulled me out of a pickle more than once.