Are you sure it's gas pipe? Maybe it's an illusion but the outer diameter of the seat post looks large relative to the outer diameter of the seat tube. That would indicate thin wall tubing. What are the outer diameters of the seat tube and seat post?
Back in the mid 1970s, there was a young (pee-wee or minime class) racer in the GTA with a small, custom built, Reynolds 531DB frame, decked out with small tubulars and 1st generation Campagnolo Super Record. His bicycle was the envy of many Senior class racers and it always attracted a big crowd whenever he showed up at an event.