"Roland Perry" wrote in message
...
In message , at
21:05:16 on Mon, 14 Jul 2014, Tim Woodall
remarked:
Z1-Euston Square on a second PAYG card 2.20
Euston to Watford Junction on my main PAYG card 3:10

Doing it all on my main PAYG card cost me 8.90
...
As an aside, I thought using oyster was supposed to guarantee the
cheapest journey. Even without the gold card, doing my journey on two
cards is 6.90.

All they say is that using Oyster is cheaper than either:

*a* paper ticket (probably some form of Travelcard) that would have
enabled all your journeys that day.

a series of paper singles.

and it's particularly bad at penalising you if you make a single peak
journey, only capping you at the peak cap instead of peak cap plus single
fare for peak journey.

It even does this if the peak journey is a bus journey that has no concept
of differential fares for TOD (and might even be considered as "free" if you
exceed the bus cap for the day).

(I have no experience of it actually doing this, the above has come from
reading the explanations, very very carefully)

tim