I think a good way to say it is that a finger release depends on the arrow to flex at the right frequency, unlike an arrow launched with a release.
I really have to think this through carefully. There are so many variables to play with in arrow design. Some variables are good up to a point, then get bad again when taken too far. It also depends on the characteristics of the bow and how it is set up, and how the arrow is released and supported. It is really easy to seem contradictory sometimes.
My footbow arrows are an extreme example. Over time, the best performing arrows are on the edge of aerodynamic instability. They are very short and very stiff. The average density of the rear half of the arrow is higher than the average density of the front half. The forward half of the arrow has more thickness than the rear half, and the center of balance is usually pretty close to the middle. They depend on a mild spin rate to keep from flipping sideways when they attain their lowest speed at the top of the trajectory. They correct their orientation to align with the direction of travel very slowly. If hit with a sidewind, they don’t even “weathervane” like a typical target arrow. But this kind of arrow only works if it is launched with almost perfect alignment. A little misalignment at launch can cost hundreds of yards.
When I built an arrow with similar characteristics for a finger-shooter, the results were terrible. If the arrow left the bow slightly misaligned, it stayed that way for a long time and bled off a lot is speed while it lethargically continued to wobble about.
Alan
