I live in the approach to/from Eglin’s runway..........................
I’ve flown in fly-bys. They are actually good practice in terms of obeying the ATC rules, which are very restrictive. And trying to get everything perfect versus good enough. You fly a lot of formation for a variety of reasons but a flyby makes you notice every detail.
Wouldn’t want and wouldn’t need to do them daily. Over 25 years I only took part in a handful.But they aren’t a waste of flight time.