John Williamson writes:

On 29/03/2019 00:48, Richard J. wrote:
In reply to this post from Theo
to onÂ* 28 Mar 2019 at 16:52 ...

Travelling on a Sunday in the winter, try Bourg St Maurice to Stratford
International. I make 5 changes:

Bourg St Maurice - Moutiers-Salins-Bride-les-Bains - Paris Gare de Lyon -
Chatelet les Halles - Paris Gare du Nord - Ashford/Ebbsfleet
International -
Stratford International

(on weekdays the ski train stops at Ashford.Â* I don't know if there are
direct trains from Moutiers to Lille in the winter which would cut the
changes to 3)

Theo

A "sensible & perfectly informed passenger" would know that you can
get from Gare de Lyon to Gare du Nord by RER D without the need to
change at Châtelet-Les-Halles.

I read the original post as applying to journeys on a single line, not
one where you change lines on the way.

Yes, that’s what I meant, at first. This all came from a genuine journey
I was planning (Oxford to Hanwell), I came up with the two�change
journey myself and then decided to see what Network Rail’s Journey
Planner made of it. I thought the Journey Planner would always come up
with a boring but “sensible� one change plan, and was slightly surprised
when it came up with the double change plan too (only for certain
departure times, of course). I then began to wonder if a higher number
of changes could ever be required, and thought this might happen where
several different services (partly) share the same route. But I’m
struggling to make the conditions of the puzzle really concrete.

[...]

--
Ian â—Ž