shock.....mmmm

shock means bad result ,right? ok lets say it is a shock , but what is appearing that is a kind of acceptable

control .isnt it?

PID is one method that allows you to alter the behaviour of an existing closed loop negative feedback system, as we would expect for any controller. If the system without the controller can be characterised (where parameters of the original system can be measured or determined so that a mathematical model of it is able to model the original system's behaviour), then it might be possible to alter the original system's behaviour in a predictable (using a mathematical model) way by adding a PID controller having a given set of P and I and D amplification factors.

But..... for cases where we haven't yet characterised a particular system, people can still add a PID controller to alter the system behaviour......and this particular PID approach will be a trial and error (blind) approach, where we keep blindly tinkering with the P and I and D amplification factors until we come up with a combination that makes the system behave in the way we want..... more or less.

At the moment, the questions you are asking don't make sense because you're not clearly explaining your ideas with control system diagrams. So show your ideas with control system block diagrams and/or control systems formula, to make your ideas clear and understandable to all.

You mentioned 'more stable' with your particular control 'technique'. Does that mean 'more stable' only because you didn't manage to understand your system well enough to achieve a stable set of PID parameter values?

When presenting and comparing results..... it's necessary to show diagrams, formula used, etc. At the moment, the details you provided are somewhat vague.

Your opening post..... you mentioned "error = gyrovalue-setpoint". You do understand that the error signal is the output of the 'differencing' (subtracting) device of the closed loop control system right? And the controller...... such as a PID controller .... can be made to operate on the 'error signal'. It is one method of changing the system behaviour.