the 955, and other watches as well, indicate which heart rate zones you were in during the exercise.
I really appreciate this UI, but I also really miss it when I review the exercise in the Garmin Connect app.
The Garmin Connect app shows HR zones like this:
I'd love it, if heart rate zones where indicated in the graph as well. It would help me to understand if I am following my training exercise as I am suppose. And since I train based on heart rate zones, then that would be very valuable data.
I understand that I can see how much time I spent in each of the zones (at the bottom of the summary), but I find it valuable to know when during the exercise I was in the various zones.