The £3 deposit can be recouped from two journeys from next year so its hardly
a moot point.

Cash - 2 x Zone 2 (£3) singles = £6

Oyster - 2 x Zone 2 (£1) prepay = £2 (+ £3 deposit) = £5

Not only recouped but a pound saved.

A very basic fact the anti-Oyster brigade seem incapable of
understanding!

The *minimum* cash fare of £3 will get the message home.
I don't think people quite understand the implication of it just yet.

From January just going one stop, even in zone 6, and paying cash
is going to cost £3 (instead of £1 on Oyster). This is a mark-up of 200%.
If this is prominently advertised at the ticket machines and explained
properly by staff surely only the insane would resist migration to Oyster?