I asked DT the same [I normally get one of 2 answers from him, either very very basic or incredibly deep that goes over my head] : ...
basically, 558 does make a lot of turbulence but as long as you are aware of it as the Reds would be it shouldn't be a problem, I remember when DT spoke to them last year he gave them some figures, distances etc, so as long as they stay out of the 'tail sector' ie; close to the rear tail cone, it shouldn't be too bad. Obviously if they are manoeuvring the turbulence spreads &, if you notice the guy line astern he is slightly low & to left. [I expect I would find it turbulent anyway

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It was also noticeable I thought that the Reds were not as steady as they normally are, but DT said it's because weren't as tight as normal so any movement is more noticable......I thought it maybe flying over water that would have had an effect but apparently not unless it was hazy, but it is difficult to tell from that video.
But must say I think all formation flying is awesome I have no idea how they maintain the distances