Author forgot to add that clients also work only 90% of time (I'm looking at you, expensive Samsung and Apple phones). So in case of Router plus AP you get 0.90

Author forgot to add that clients also work only 90% of time (I'm looking at you, expensive Samsung and Apple phones). So in case of Router plus AP you get 0.90.90.9 = 72% reliability. Basically wifi is a mess.