I agree that South East London needs better transport, and that Crossrail
isn't it. (I think it's mildly ridiculous that it won't serve Woolwich, for
a start). But I definitely don't think it's TL2000 - if I was living in,
say, Eltham and could choose between two trains per hour to Charing Cross
and two more onto Thameslink, and four to Charing Cross, I'd choose the
latter.* The train services in South East London are appalling, and sending
a few of them to Luton isn't going to change that. What the area needs,
short of an extension of the Bakerloo line, is proper turn-up-and-go metro
services - something that TL2000 is going nowhere near providing.

Which is really an argument for one part of TL2k without the other -
the quadrupling from Met C Jct to Boro Mkt Jct and the London Bridge
station rebuild without silly dual-voltage through routings. The
problem with this is that up to 48tph might be a little much for the 6
platforms at Charing X. The solution might be a nice little bit of
tunnel - either to Victoria or to run as a Chelney style line to
Parson's Green (then Wimbledon to take over the lines to Sutton, Epsom
and Chessington).

The same functionality as TL2k with the added bonus of decongesting
London Bridge a bit would be the construction of an interchange
station in Southwark where the Holborn Line crosses over the SE Main.

*Yes I've just plucked those figures out of the air.

Regardless, you make a good point. Compare the success of
high-frequency metro lines with the mess of branching low-frequency
routes in South London.