The main point about BA club Europe for me is the meal. Being diabetic, i need a meal, not a sandwich. Going Club means that I can leave the office in Stockholm at 1830, rather than about 1300. With my time charged at $150 an hour (I wish I got that!), business class makes sense.
Sometimes, though, the last flight from Nice on a Friday is so popular that the fare is more than twice the usual,- in all classes, and it works out cheaper to stay overnight in Juan les Pins.
I figure that airfare pricing is an arcane art, and Relativity, quantum mechanics and advanced mathematics are more easily understood.