I think people mistake a centerboard for something that will snap your neck when you lower it, like a Turbo-charger or something.
All the centerboard can do is provide added lift. 'Lift' helps a sailboat go to windward. You don't 'feel' it sailing to windward. At it's best, the added lift simply improves the boats actual course to windward, over the ground. Nothing changes on deck, the boat or the sails angle(s).
That's why many people say, "I never see any change so just leave the centerboard up" There is nothing to see an not much to feel.
I can often see the result of the additional 4' of lowered centerboard by an increase in the angle to the wind the boat will make to windward, on the GPS chartplotter. This is revealed in the heading into the wind narrowing by a few degrees, or the icons pointer on the screen swinging a few degrees closer to the wind. Nothing else on deck changes, this is simply the lift working to increase course to windward.
I'm happy to see 5 degrees improvement to windward, but with all the factors involved (current, wind, wave action and on and on,...) in practice it's often less.