Hi. I find the default value of `mouse-wheel-scroll-amount'
mysterious. Jumping 5 lines at the time per scroll event (plus more
when `mouse-wheel-progressive-speed' is enabled, which it is by
default) makes the scrolling feel very "nervous". It's also hard for
the eyes to follow the text when it makes such big jumps.

It's especially bad in the cases where it's hard to control each
scroll event, such as with laptop touchpads or with ThinkPad-style
trackpoints. Then I find the default scrolling mechanism next to
unusable.

Does anyone else feel the same way? If more people agree with this, I
propose setting the default scroll amount to 2, or maybe even 1. I
also find that the progressive scroll speed functionality contributes
to this "nervous" scroll feeling, and I propose turning that off by
default as well.

This will make scrolling Emacs behave more similar to other
applications, and I think it will provide a more pleasant scrolling
experience.

-- Simen