On Sat, 14 Jun 2008 20:16:20 +0100, Dave Newt wrote:

If you're travelling from an LU station to an NR or DLR station that
doesn't have gates and you're also travelling back the same route -
don't bother touching in or out at your destination. Just touch out at
your home station when you get back and you'll be charged the 4 quid
maximum single fare - less than for a return journey from most outer
stations.
B2003
Wouldn't that be eight squids rather than four?

Nope , it only deducts a single journey. Presumably thats the penalty
fare if you realise you've forgotten something on your way to work or
wherever and have to return home so touch in and out at the same
station.

Isn't anything longer than two hours assumed to be two separate journeys?

According to a London Lite article I posted about here around 6 months
ago, the charges for touching in then out at the same station a

- Within 15 minutes: no charge
- Over 15 minutes apart: £8

I've never tried it, though.