Also after the flight the instructor can refuse to sign of any 1hr dual if he/she isn't satisfied with the standard of flying
Well, this is the bit that I don't agree with. You've booked a flight lesson, irrespective of its final purpose. You've had the lesson, the instructor was PIC and you were PUT. On what grounds can the instructor refuse to sign? After all, he's instructing, not examining.
And if the instructor refuses to sign, what goes in your logbook?
Mind you, I agree that that one hour training flight is best spent doing a good workout. Stalls, PFLs etc. And if the instructor is not happy, I don't mind a comment in the logbook or somewhere else "further training in XXX recommended". Also, if the flight doubles as a club check, I fully understand that on behalf of the club the instructor tells you that you are not to hire their aircraft until you've had more training in YYY. But for JAA revalidation, all that's required is a one-hour training flight. Nothing more nothing less..