I did a tour of the ground when I was about 10/11 (73'74 Shilton was still there!). We were told that the original plan was to have the pitch at 90 degrees to how it was. The electricity board built a substation behind the West (Main) Stand and this prevented them expanding in that direction. They were also buying the houses along Burnmoor Street and only needed 4 to complete the whole Terrace. The Plan then was to knock them down and build a new stand. However the club sold them all off in the '80's when they were skint and crowds of about 10K meant they thought they'd never need a bigger stadium.