The line presented the Metropolitan with a problem – so successful was the suburban traffic that, by the early 1930s, the lines into Baker Street were becoming overloaded, a problem which was exacerbated by the post-war flight from the City of London to the West End of London.
Banen gav Metropolitan et problem – forstadstrafikken var så vellykket i 1930'erne, at banerne til Baker Street blev overbelastet, et problem der blev forstærket af flugten fra City of London til West End i efterkrigstiden.