A stack-to-reach ratio above 1.55 puts you in a very upright, relaxed position on the bike — and yes, that's still a legitimate road bike geometry, just designed with comfort as the top priority. This ratio means the frame is significantly taller relative to how far you reach forward, so you'll sit more vertically with less weight on your hands and less strain on your back and neck.
This makes the most sense if you have flexibility limitations, lower back issues, or simply want to enjoy long days in the saddle without feeling folded in half. It's also a great choice for long-distance touring or century rides where staying comfortable hour after hour matters more than slicing through the wind.
The tradeoff is real, though: at higher speeds you'll catch more wind and work harder against it compared to a lower, more aerodynamic position. If you're not racing or chasing fast group rides, that's probably a worthwhile exchange for the comfort you gain.