After seeing it mentioned somewhere I decided to see if there was a configuration option in about:config for controlling the number of lines scrolled with the mouse wheel. Turns out there is.
Like IE, Firefox is pulling the number of lines from the OS; but it uses a different calculation to determine exactly how big a line is. If I open up IE and scroll my mouse one click down on Yahoo’s front page, the top of the window rests right under the line below the tabs for the search box. In Firefox it would stop right after the Yahoo banner at the top. A large difference even before you consider that when loaded in Firefox the tabs are replaced with a combobox to the right of the search text, so it has to scroll even further in IE than Firefox just to get to the textbox.
As I mentioned in the first paragraph the fix lies in about:config. Scroll down to the lines that read “mousewheel.withnokey”, change the one that ends with “sysnumlines” to false, and set the one that ends with “numlines” to the number you desire (the default is but the user can change the system value in the control panel). I chose 6. Now you should have nice fast scrolls once again, and my finger can begin to recoup after all the extra time I spent scrolling.