Getting back to the original point of the in-car line diagrams, would
this not simply come down to costs? Presumably it'd be cheaper to
order (say) 10000 maps, all printed East - West, rather than a batch
of 5000 E-W and 5000 W-E. Plus, they'd save the cost of someone
sitting down in front of a computer making the 'second' version of the
map.

Maybe.

M