My train setup is probaly somewhat special as my intercity trains, high-speed or not, for the most part only stop at two stations. (Difficult to match capacity and demand otherwise.) My passenger trains also have a dedicated platform, with only a few lesser lines sharing a platform. Freight lines often run orthogonally to the passenger lines. As such, my high-speed trains have dedicated lines as a more natural consequence of how the network forms than by concious design. As tracks converge just outside or inside cities, high-speed and non-highspeed lines may converge for a few signal blocks. In a few instances, I've built four-tracked lines, when some freight lines have happened to be able to share tracks with a passenger line, only for me having to separate them when top-speed for passenger trains significantly differ from freight. In these cases, it's actually the freight tracks that must bypass the stations.