Great points, and nice to see people agreeing with me for a change :-))

One quick question (on behalf of my wife, who has a 1-3 annual ticket on
her Oyster, but with £20 on top for whenever she may go out of zone...

What happens if she forgets to touch out at Plaistow (the gates are always
open) under the new rules?

Will she be charged £4 from her contingency pre-pay for not ending the
journey? Or are people with season tickets not charged in this way?