They were hardworking and disciplined. While Indians were engaged in hard labour, the british provided the technical skills and equipments, and helped work lines which back then was regarded as one of the toughest ever built. Since they worked in a tropical country which has tropical diseases(and weren't immune to it) many of them died too.

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Bureaucracy is a unique aspect of democracy. Autocrats and kings of the world are unlikely to show patience with their 'babus' delaying things they want done!
I agree with you on the altruism concept on foreign lands. I was just trying to outline why it takes much longer to build route lengths post-independence. The one additional factor is political apathy because most RMs have focussed on building immediate political capital by announcing new trains rather than spend money on infrastructure. There is a big scope for improvement on that front.

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The main cause of rapid expansion of rail networks under the Crown was easy or huge capital investments available for it's construction and less red-tapism of bureaucracy.
Apart that nothing was special - Bristish provided technology & natives were toiling hard.
Apart this Indian rail line workers were also taken to Africa by Britishers for railway construction, as they found Indians very good at rail line construction (especially Mistry community of Western India).
Thanks!

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