On the workout screen, when set to imperial units, the speed and distance are displayed as the metric value with an imperial label.
As much as I wish 136 W would get me to 27.8 mph, unfortunately it doesn’t. It should be 17.2 mph (which is 27.8 kph). Same goes for the distance, it’s displaying the kilometer distance with a miles label (it should be 19.65 miles which is 31.6 km).