There's a pretty staggering issue with the daily suggested workouts being based on pace rather than HR Zone, especially considering the intent of the suggestions. I live in a fairly hilly area and my watch beeps at me over, and over, and over, when I'm going up steep hills because I'm going to slow, but when I'm supposed to be doing a recovery run I should really be walking up these hills if anything. Running at a 10 minute/mile pace up some of these steep hills easily puts me up against Z5, but even running in Z4 (on a Recovery Run, mind you) has my watching beeping incessantly that I'm running too slow.
If I could tell my watch to beep at me when I'm outside of the appropriate HR Zone rather than outside of the pace range it would be way more versatile across all terrains and weather, and wouldn't be obnoxiously egging me on to train improperly.
