True, but just passing through stations often means slowing down to less-than-blazing speeds. Also, you must account for the possibility of the faster trains ne

True, but just passing through stations often means slowing down to less-than-blazing speeds. Also, you must account for the possibility of the faster trains needing some way to pass slower ones. This might mean more track infrastructure to allow the slower ones to pass to a side track. It might also mean that the slow train's having to wait slows it down further, making running them on high-speed infrastructure a questionable idea. I trust that the French made the right decision. Germany has fast trains that stop at more places than the French, and in my experience they don't have the theoretical fast trains that just pass through almost all stations with very few stops. Presumably because it's hard to make it work.