In message
-sept
ember.org, at 15:52:40 on Thu, 25 May 2017, Recliner
remarked:

Does HEx have to continue to terminate at Paddington? Can't it go nonstop
to Paddington and then continue to Abbey Wood with the same stops as what
will replace Heathrow Connect?

Even if that were possible, how could it attract a premium fare in such a
case? And how could such a premium fare be enforced?

On-board grippers, like they use today. For the leg from the airport to
Paddington, anyway. The rest they'd have offer interavailable ticketing
with Crossrail, which of course would abstract revenue from TfL.
--
Roland Perry