On this question of how and why things could be done quicker in the old days:
A while back I read a very interesting book about the electrification of Manchester-Crewe. Two things stick in my mind from that book.
Bridges can't fit the wiring in? Blow them up! (No Listed bridges back then.#)
London Road needs rebuilding. A photograph showing how they removed the brickwork from the top of the old station. Bloke on the roof, no harness, no hard hat, crowbarring the coping stones onto the pavement many, many feet below!
Wouldn't be allowed now. H&S gone mad!
# Okay, a few may have been - Royal Border, Royal Albert etc, but not wayside country roadbridges.