> Test and measure. If you can't measure the difference, it doesn't matter. If you don't measure the difference, the rule you are following probably isn't helping you.
/Yes/.
/Yes/.
Unfortunately that day is already today on the Internet, where browsers have unknown design decisions made of unknown reasoning across networks that were optimized for unknown requirements.
We have decades of it, it's so trusted that you're forgetting it even exists. What we don't have are convenient answers for questions at the edge of predictability involving dozens of constantly-moving variables.