Here's something to ponder:

if you swatch for something, get gauge, and then don't cast on to knit it for more than a week, do you need to swatch again?

I never did get around to casting on for that furry vest out of the winter '00 Vogue Knits.

My gauge stays pretty consistent - I can put down a project for a couple weeks and not notice a change when I pick it back up - so I'm guessing that for me, the answer is "no".

I will check the measurements after the first several rows of knitting and rip back if necessary. I don't want to swatch that stuff again.