> Shouldn't step 2 be "wash carefully with warm water and soap"?
In theory, yes. In practice, lots of people in public restrooms just wet their hands under the faucet, without washing them, and then go immediately to the dryer.
Not everyone does that and the point of the study was to figure out what happens if people with dirty hands use towels, dyson blades and other hand driers.
I sat outside an ICU once. At a not-first-rate US hospital. The handle-pull door was plastered with signs, variously saying "use hand sanitizer before opening door". It was right next to the door. It worked. There wasn't an alternative one inside. That it wasn't used by the traffic back and forth to the adjacent bathroom, seemed odd. The nurse who also flushed (hand lever), without associated sink noise, was a bit boggling. The error induced mortality which occurred shortly thereafter, did not entirely surprise.
In theory, yes. In practice, lots of people in public restrooms just wet their hands under the faucet, without washing them, and then go immediately to the dryer.
Cf. the Assume a Can-Opener fallacy https://en.wikipedia.org/wiki/Assume_a_can_opener