Assume that I have a heat map UI showing company stocks. The current pattern that users have been exposed to for the past 2 years is dark green being low value and light green being high value. To me, this seemed a bit counterintuitive since a darker shade of a color means "more" and lighter shade of a color means "less." I tested a pattern with the rules swapped (dark green as high value and light green as low) with some users, and they didn't even notice the color swap. In fact, they were able to describe the rules of the color pattern.
Are there any precedents of a website or app swapping a pattern or changing a designated rule if the learned legacy pattern is tested as less intuitive? Or is this a UX no-no?