Every loft deals with the same short list, and almost everyone follows a routine they were taught rather than one a vet designed.
The part worth arguing about is calendar dosing — medicating whether or not the birds are ill. That is exactly how resistance builds, so the drug stops working in the year you actually need it.
What do you give, how often, and do you treat preventively or only on symptoms? And has anyone here found a vet who genuinely knows pigeons?