Felt inspired this morning, so dusted off my old mountain bike (a 1992 GT) and tested the journey.
Just under 10 miles, mostly flat and did it in 65 minutes, so 9mph average. Had to then bike a mile up the hill to get the train home as I was very tired, that was much slower in granny gears. Certainly doable without an ebike but I think if I'm doing both directions a more sedate ride in and a blast home would work nicely. If I can get the time down to 45 mins so much the better, that'll be the aim. Incidently, being heavy isnt great on a bike with no suspension!