And that "if" turns into a delay hugely chewing up the benefits of such high speed. There was, briefly, a rather grand project implementing a "fast ferry" betw

And that "if" turns into a delay hugely chewing up the benefits of such high speed. There was, briefly, a rather grand project implementing a "fast ferry" between Toronto (Canada) to Rochester (New York). This cut the previously 3-hour drive around the intervening lake down to about 30-45 minutes, and included the luxury of enjoying the view/bar/games/social. Price wasn't bad (comparable to gas cost for the long trip), but certainly not trivial. Anyone coming to Rochester discovered "they come down far from a desirable location": having no personal transportation immediately available, it was upwards of an hour to take a bus from the port to downtown Rochester - turning an ~80% reduction in travel time to ~40%. The project was scrapped - twice[1] - after enormous expense. When throwing lots of money at diminishing returns, encroachments on those returns are very costly. [1] - There was huge political capital invested in the ferry's success. Upon completion, ridership was dismal and the project went bankrupt within a couple months and the boat went up for auction (few want such a specialized vessel). City-scale egos intervened and bought the boat back (!) at the auction, pressed it back into service. The mayor et al were promptly voted out of office, and the replacement sold the boat and permanently shut the project down.