With regard to my earlier post about the Maindee curve, it's not just my ramblings, Sewta have called for a direct AGV - PAD service:
SEWTA CALLS FOR IMPROVED GREATER WESTERN FRANCHISE
Date posted: 27 April 12
Regional Transport Consortium Sewta has responded to the Governments Greater Western Franchise replacement consultation by calling for existing services to be retained with improved frequency and capacity, and the new franchisee to commit fully to electrification.
Sewta (the South East Wales Transport Alliance) who co-ordinate transport strategy, plans and programmes for the 10 local councils of South East Wales makes the submission in a 25 page document Sewtas Response: Department for Transport - Great Western Franchise Replacement Consultation. The new franchise will start operating in April 2013.
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Sewta also highlights aspirational new services that would benefit both potential passengers and the Welsh economy if included in the new franchise:
Abergavenny to London once a day in each direction, calling at, Pontypool and New Inn, Cwmbran and Severn Tunnel Junction to arrive in London before 10am, and departure from London before 8 pm.
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Full article
Here
In my mind, this would involve using the curve as they don't mention calling at Newport, this would also avoid reversing at Newport.
Gareth