I'm currently studying as a piano technician, and I'm just starting to learn how to tune a piano. I want to tune it a few times before going out and doing others people's pianos, but I'm not sure what the best approach for practice is.
I'm wondering if I should detune my piano slightly (either in small sections or fully) so I can tune it again. Is there a better way to go about this? Will this have any negative effects on the instrument? Would it even be better to just do it once, and then go out and get some experience on other pianos?
I should add that I'm taking an online, at-your-own-pace course (Piano Technician Academy), so I don't have a given instructor / mentor available.