If you have a problem navigating at a cycling pace, you have more serious issues.
It can be pretty serious, all right. My last crash happened when the pack came to a fork in the road and the guys in the front hadn't been paying attention to the route sheet. FWIW, though, in my cycling club, we print out an easily-readable list of turns and mileages, which riders clip to the handlebar or brake cable, and this has generally worked pretty well for the 30 years I've been riding with bike clubs. And when I'm mapping out a route for myself in unfamiliar territory, I write a similar route sheet.
One potential problem with the Hammerhead is that bicyclists sometimes ride in places where there is no cell phone service. I've tried using Google Maps on occasion (while stopped on the side of the road), and the map information simply isn't there. The Garmin solutions are far better than the phone.