We should fight back during checks, if we percieve something wrong.
Ooo I'd be very careful about recommending check-ees to 'fight back' during a checkride. Especially when they 'perceive' something to be wrong.
We already have enough arrogant, ignorant and/or misinformed pilots (which is not necessarily the pilot's fault) out there that this is not a recommendation to just pass out. There are many things that you will be taught that could actually be wrong even though they make perfect sense to you. If you 'perceive' something to be wrong, DO NOT fight with your examiner. When the time is appropriate ask your examiner to explain what you didn't understand. The majority of the time your examiner will be correct. These usually come down to a misunderstanding but in any case, during the ride is not the place to be discussing how you think the examiner is wrong.
The way to 'fight back' is to talk to someone in a higher position that will listen to your complaint and take notice. When a number of people have complained about the same thing, something will be done. If nothing is being done, you're talking to the wrong person!