I believe it is designed to come up with any other stations with the term 'York' in them which could come in useful if you cannot remember the full name or spelling but remember it has a particular combination of letters in it. You may sometimes see the station name and think "oh yes, that'ds the one!".
York Bently(South Yorks) [to distinguish from Bently, Hampshire or Great Bently, Essex(?)] Clapham(North Yorkshire) [to distinguish from Clapham Junction or Clapham High Street, London] Swinton(Yorks) [to distinguish from Swinton, Greater Manchester]
You can now use the 3 letter station codes in the journey planner and in all of the live departure boards - I find that memorising the ones I use most often helps because it's quicker and prevents the system asking you to confirm it.
Tubetrack doesn't give you the choice of the 4 stations when you search for York - it automatically goes for the main station. But if you put in London or Birmingham, for example, it would give you all the stations for that city (Birmingham New Street, Snow Hill and Moor Street) and I suspect when given London it could very easily not just give you all the termini but also all the railway stations and possibly all the tube stations as well!
Can't get National Rail to spell it 'Bently' myself! Entering Bentley gives the choice of Bentley, Bentley (South Yorks.) and Great Bentley, whereas entering Bently gives the same three (spelt correctly!) as well as Beauly and Huntly. Not quite like the village of Whittlesey, known (officially) to the railway as Whittlesea .