I agree partially, because most coaches will tell you about doing what feels natural, but this means only up to a certain point. Some things can be done in a variety of different ways, so a fighter can do it the way that's more comfortable to him as long as it's still within the range of good form.
However, some things are just bad form and any coach/trainer will say so. Example: One fighter throws a jab and moves his arm so the shoulder raises a little, giving some protection to the side of the head.
A second fighter doesn't do this, but does duck his head down a little as he throws. Neither fighter would be yelled at for being wrong.
A third fighter throws his jab both tucking his head down and protecting it with the shoulder, then instead of bringing his hand straight back, he brings it back below chest level.
The third fighter will get called out for this because even though it was more comfortable to do so, it will get him counterpunched.