Not to a degree that you, as a beginner, would ever notice it. And by using the dual rate, as soon as you felt confident, and he agreed, all you would have to do is flip one switch to get full throws back. You could then fly it around and get comfortable with it there. Finally, when ready to land or for any other reason, flip the switch back to low rate and be right back to the trainer throws you WERE comfortable with.
Personally, I've never concerned myself with the "sensitivity" issue as I feel it is overthought. I use Dual Rates on my planes. I also don't use Expo because I don't care for the "feel" it gives the sticks. But to each his own. Experiment and see what works best for YOU.

These are my opinions and we all have some.

BTW - if you do use dual rates, that adds another switch to the preflight that MUST be in the correct position or you may get a surprise.