Mike Bristow ) gurgled happily, sounding much like they were
saying :

these staff wouldn't have an interface with Oyster.

Why not? Ticket inspectors already have hand-held Oyster wands.

That may not be sufficent for the more complex problems[1]. Y'know,
the ones the machines can't cope with, and that a person at a ticket
office needs to resolve.

The ones a person needs to resolve? Yeh, I'd reckon that could be arranged.
All you'd need to do is have a person holding the wand, and have a wand
with sufficient software. Shouldn't be difficult. Build a cheap PDA into
it.