- Is there a minimize traffic to the website required to get statistically significant results? Or does it matter since you're trying to move the site up in the Google ranking?
- Does site traffic affect the length of time it takes to test?
Good question -- all of the things you mention are factors. It's harder to run statistically significant experiments with really small sites that have few pages. The factors involved are: # of total pages, search traffic, and Google crawl rate.