Question

Does anyone know if there is a way to determine whether a segue with a particular name exists? Or alternatively, if there’s a way to get a list of all the named segues that iOS knows about

Answer 1

no, your method only detect when a particular segue is fired.
but you can’t test if a segue exist, by another way than try to call it.
it seems that the only way is to use @try @catch :

@try {
    [self performSegueWithIdentifier:@"Replace_Connected" sender:self];
}
@catch (NSException *exception) {
    NSLog(@"%@  no segue with identifier 'Replace_Connected' : %@", [self description], exception);
}
@finally {    }