John B wrote:

I would be surprised if more than about 5% of passengers using these
platforms can even use Oyster for their journeys and as it is the gates
cannot cope with the volume of people in the morning rush - typically
the next train has arrived before all the people from the previous
train have made it through the barriers.

Really? All DC lines (ie slow trains to Watford) stations accept Oyster
Prepay except Kilburn High Road and South Hampstead, and Oyster
travelcards are valid for all stations within zones 1-6.

There are three four carriage trains per hour on the DC line.
There are 5, 8 carriage trains leaving Watford Junction between 6am and
7am when I'm usually travelling (which don't usually have too many
problems at the barriers) and, according to the timetable, 10 trains
arriving at Euston between 8am and 9am with 8 or 12 carriages (The two
that don't stop at Watford Junction may not go to these platforms - I
know that sometimes these trains depart from platform 16)

(So it might be closer to 10% who can use Oyster)

I would say that at least half the time when I travel arriving at
Euston around 8am (which isn't that often) the barriers have been
opened just to try and get the people through with the staff shouting
"Just go straight through" while people are still fumbling with their
tickets.

I've almost never seen someone using a Oyster card at these barriers -
very occasionally someone going onto the platform. Of course, I'm in a
crowd of people most of which Oyster can't be used which will skew my
observations.

But from your comment, does that mean that Oyster prepay can be used
all the way to Watford? Even on the fast trains?. On the trains I
travel on I've never seen anybody present an Oyster card to the guard
when they do a ticket inspection.

Tim.