Well, if he based his decision on how you were scoring during practice, he's not the brightest bulb on the tree anyhow. I don't know about you, but I use practice time to work on things, not to score. As such, I may just shoot at spares out of full racks, try different balls, different lines, different hand positions, etc. I'm not really looking at what the score ends up being. I actually just prefer to have them turn the scoring off so that it's not even a temptation for me to worry about it. I think that's how most people practice.