I know of one rescue that didn't go smoothly because there was confusion between degrees, minutes, seconds and decimal degrees.
You could just read off a fractional N-W GPS coordinate like an average person. Every smartphone comes with a GPS app these days.
Assuming you're reading these values off a device, most can display them in various different formats. It's pretty confusing and converting them isn't easy either.
Yes, but does a system which uses singular and plural of words as a distinguishing feature really help here. (not saying that there couldnt be a better system based on words)
It's easier to get confused. And there's still ambiguity. A few months back I was fighting my phone over this--typing degrees/minutes/seconds into Google on a phone isn't easy. I ended up using the calculator to convert it to degrees with fractions. Finding the spot along the road was a pain.