Sir Leslie Wilson was the governor of Bombay(now called Mumbai), hence it was named after him. The first electrified section, IIRC, in India was around ~1930 in then Bombay - Poona.
Fun fact: the Deccan Queen train in this sector was faster when introduced 95 years earlier than it is today mainly because it has two extra stops now.
Yes, even now majority of trains require two technical halts in that sector for attachment and detachment of bankers respectively.