Good point about the silly 'fast jet' appellation used by the RAF.
It came in when aircraft like the Jaguar, Harrier, Buccaneer and Tornado came into service. The fighter pilot ego simply couldn't come to terms with flying 'bombers', so a new description was introduced to keep the little dears happy.
At one point in the '70s, 208 Sqn at Honington used to say they were going to practise 'DFGA' tactics - Day Fighter Ground Attack! In Buccaneers?
I fly a jet which is pretty fast. It's a fast jet, but not a Fast Jet, 'twould seem................