Mint also has the natural effect of cooling. Since we associate cool with fresh, it makes sense that mint became known as a breath freshener. And that's more a regional thing. In other cultures they used things like licorice to freshen breath.
ETA: Putting your own corset on is much easier if it has a busk (the metal piece that lets it split in the front). Without that, you have to almost completely unlace it to get it off. And to do it up yourself you need very long laces.
The ones that went further down didn't go all the way down to the bottom of the buttocks in the back. They were also generally a less confining material.
Steel is really what changed corsets into something that can be enjoyable to wear in my opinion. It means they last longer, shape better, and do more. As a corset enthusiast (I make my own so they fit right) I love the steel bones available now, and hate the plastic things!