If you asked "the man on the street" that specific question then, yes, most would probably reply that they don't. They've probably never even thought of it before.
In my experience, most people don't know one train from another, let alone where the engines are on them. They just want a pleasant travelling experience (a seat, somewhere to put luggage, perhaps a café/trolley)
We're probably over-thinking things here, which I'm not complaining about as I am thoroughly enjoying this thread. But we have to remain aware that most of the general public don't know, and don't care what an HST is, nor about anything other than what their own journey is like. In that regard, IF the HSTs are run reliably, I can't see how this intro can fail.