Doubtless like many here, I recall the massed pass at the end of Duxford's Flying Legends. Impressive. All assembled well out over the countryside, and flying past in a steady formation, which took a considerable amount of briefing.
In contrast, looking at shots of Dallas, this seems to have been a ragged and high speed formation, in a constant left turn, done over a city. The accident aircraft were well up in the sequence, with many others being visible in various degrees of turn and spacing just behind them. Quite how someone in a close formation could even contemplate being in a 45-degree banked turn, unlikely to have been briefed, just seems extraordinary.