Putter laser pointer | Golf Monthly

As soon as you add a device to 'the system', as a measure, you affect 'the system'. Think police car sitting at the side of the road measuring speeds! Amusingly, Placebo effect is probably another example!

Golf examples that are applicable are (certainly my) Playing Lessons and attendance at a Fitting session.

Non corrupted version is a Quantum Mechanics principle - Not being able to measure both position and momentum of a quantum particle simultaneously.