The little finger whisper key, or french whisper key; should become a standard key on the bassoon. It adds an extra option besides the whisper key lock and reduces fatigue in the repeated transition from low note thumb position to the flick key thumb position. The first example comes from Robert Rønnes book “12 Virtouso Studies” in the first study “Warming Up” This passage is a good example of the low register to middle register thumb shift. The left thumb need to shift from the low C key across to the whisper key. However with the little finger whisper key, you can hold down the whisper key for the entire measure. This allows the left thumb to stay in the low register position and play low C as it comes. By using the french whisper key there is the option of quickly removing it, unlike the whisper key lock. It can be added or removed during a fast passage without a reach or shifting.
The next example comes from Simon Kovar’s “24 Daily Exercises” and is a more common issue on the bassoon, the shift from the whisper key to flick keys. The usual technique is to leave the whisper key slightly early in order to get to the flick key in time. With a french whisper key a passage like this takes minimal energy with greater accuracy.