He may have meant that the dropouts were stamped. It's hard to tell from here, but given the style of the fender eyelets on the dropouts, it seems a lot more likely that they were forged. Raleigh was a high-quality brand, and the Super Grand Prix, while far from top of the line, wasn't a particularly cheap bicycle either. Sounds like your mechanic doesn't know what he's talking about, and is a jerk besides.