> "For routes where this happened I don't see why we couldn't upgrade the stations to a bigger loading guage and have double decker trains." The costs would be

> "For routes where this happened I don't see why we couldn't upgrade the stations to a bigger loading guage and have double decker trains." The costs would be high and the benefits negligible. Where more capacity is required, it's typically easier to lengthen existing trains, or run more trains, than to go adapting stations and building new unique double-decker trains that are only going to be compatible with a specific line. And, as mentioned elsewhere, double-deckers have a big disadvantage in lengthening dwell times (due to less doors per passenger), which could result in slower services.