On Jul 9, 12:18*pm, wrote:
The difference is that no one would be dumb enough to put a single fare
paper ticket into the gate to get out again because they'd know it would
be swallowed. They'd ask the guy at the window and explain the situation.

Quite. One might have thought that no-one would be dumb enough to do
the same with Oyster, but rather would ask the guy at the window and
explain the situation.

--
John Band
john at johnband dot org
www.johnband.org