As someone who has done a fair amount of air tests and post maintenance flights I'm sorry but I cannot agree!
UV, so have I and that's why I said it.
Sure, the post maintenance flight prior to releasing the aircraft back to service may result in an increased exposure to further maintenance actions. But once released to service, there is typically no increased risk from one end of the schedule to the other. Therefore, the
average pilot is just as likely to have an engine failure (or other maintenance issue) following maintenance as they are coming up to it.
I say this having done quite a number of engine break-ins and other maintenance test flights. The only engine failure I've ever had was 5 hours prior to an inspection, but I've sent just as many airplanes back into the shop following maintenance as I've sent coming up to an inspection.