nre.co.uk* says you can use a Stamford-Cambridge ticket to travel via Stevenage (so you don't need to buy to an alternative station and not be able to, say, buy a plusbus ticket at your actual destination).
I know 700070 says "via Cambridge", but easement 700714 says:
700714 (Manual) Tickets to/from Cambridge are also valid at Cambridge North and tickets to/from Cambridge North are also valid at Cambridge. This easement covers all tickets, including season tickets, except Advance tickets.
This means that a Stamford-Cambridge ticket is valid for a Stamford-Cambridge North journey. Cambridge North is north of Cheshunt, and you would travel via both Hitchin and Cambridge so the wording of easement 700070 is satisfied. You can, of course, finish your journey early at Cambridge.
This clearly isn't what nre.co.uk is doing, but it gives the same end result.
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