There’s a common idea with woodwind players and teachers that it’s important to keep your fingers close to the keys. Keeping the fingers within a certain reasonable distance does have benefits:
- It’s easier to keep track of where the keys are and not “miss,” especially for beginners
- Allowing the fingers to rise too far can introduce tension into the hands
But I think finger-closeness is a concept that gets over-taught and over-stressed. It seems to be motivated by a desire for finger speed (or some euphemism like “fluidity”).
Assuming the fingers are within a reasonable range, I think working toward extreme closeness probably doesn’t offer much if any speed increase, but does make tension more likely. It’s a micro-optimization only worth thinking about when you’ve solved every other problem with your technique, and even then your results may differ on whether it’s productive (or even counterproductive). Definitely don’t stress out your beginning students over it.
Try this if you like: bring a finger down onto a key from, say, 1-2mm above the key (about the thickness of a couple of credit or ID cards). Then try from ten times that distance, 1-2 cm (the width of a fingernail or two). What do you notice about speed? How about tension?
Keep the fingers close enough to stay in position and not bend backward, but don’t worry too much about dialing in extreme closeness.