Access Paths

I have been taking a look into the tram line feature in AgOpenGPS and have been wondering what it would take to modify it for creating access paths in the field.

What I mean by access paths is after a set number of swaths, the AB line is shifted over a set distance to create a driveway. I have attached a picture that shows how we leave irrigation driveways in the field that are 20 swaths apart.

I though I would see if anyone else has use for a feature like this or if it has already been done.

Any thoughts on this would be appreciated.