Perhaps someone better versed in London's transit history can help but I think that one thing which is giving First Gulf some trouble with pre-leasing here is the degree of uncertainty in the transit planning. Sure we've got plans for a number of different lines utilizing different technologies but Toronto is notorious for planning and, in the case of Eglinton, even starting construction before a change in government priorities causes everything to grind to a halt.
Was the Jubilee Line extension under construction in the early 90s when CW debuted to catastrophic failure? CW Underground station opened in 1999 but was the broader line in planning or under construction 10 years before that?
From Wiki:
The extension was authorised in 1990. A station was originally planned at
Blackwall, but this was replaced by diverting the line between Canary Wharf and Stratford underneath the Thames to serve the
Greenwich peninsula at
North Greenwich station. Plans for the
Millennium Dome did not yet exist, and this diversion was made to provide for a planned housing development on the site of disused gasworks.
British Gas plc contributed £25 million to the scheme.
[3] The stations at Southwark and Bermondsey were not initially certain.
[4] Main works were authorised by the London Underground Act 1992,
[5] with additional works allowed by the London Underground (Jubilee) Act 1993.
[6]
Construction officially started in December 1993, expected to take 53 months.
[7] Tunnelling was delayed after a collapse during the
Heathrow Express project in October 1994, which used the same
New Austrian Tunnelling method.
[8] By November 1997 a September 1998 date was planned.
[9] By June 1998, opening was planned in Spring 1999.
[10] By November 1998, a phased opening, previously rejected, was being considered, with Stratford to North Greenwich planned for spring 1999, to Waterloo for summer 1999, and the link to the Jubilee line for autumn 1999.
[11][12] This scheme was followed, with the first phase opening on 14 May 1999, the second on 24 September, and the third on 20 November. Westminster, complicated by the interface with the subsurface platforms, which remained in operation, opened on 22 December 1999, shortly before the
Millennium Dome deadline.
[13] By February 1999, however, the cost of the extension had gone up to a total of £3.3 billion.
[14]
https://en.wikipedia.org/wiki/Jubilee_Line_Extension
AoD