Well whoever built the Oilrig, I still believe that it is an inferior build to Trainyard.
I think Bushi spent quite some time on Trainyard as it was showcasing T+T in its prime
Oil Rig is what I believe to be one of his quick builds for instant DM action
Trainyard is much larger and has more aspects compared to Oil Rig, but I like Oil Rig for its instant hot-blooded action