After about two months I finally just looked on Google.  I searched on something vague, like the mouse didn’t feel right or something like that.  Lo and behold the answer to my question was there; it was the mouse acceleration curve.

Turns out, somewhere along the line between Mac OS 9 and Mac OS X 10.5 Apple decided to quietly change the acceleration curve on the Mac.  The result is an acceleration cliff; the mouse moves quickly and then, right before the target it slows down…to a crawl.  Normally the mouse would slow down incrementally, gradually, allowing the person to place the pointer directly on the target.  Once the mouse slows down it creeps across the screen.  This was causing me to overcompensate and making my arm ache after a while.

I’m not the only one who has problems with this.  Traci, on the other hand, can’t seem to notice a difference and has no problem at all.  Some Mac heads will defend this behavior because of an undying allegiance with the almighty Apple.  That’s bullshit.  Linux does not suffer from this problem; the acceleration curve provided by X is just right like *gasp* Microsoft Windows.  Turns out Microsoft got this right.  They’ve done a lot of work on pointer ballistics and have put a lot of thought into the mouse on their systems.  I’m not part of the Apple cult; I love my Mac and I’m fond of Apple but they screwed this one up.  They don’t even offer a way to modify the curve, just the cursor speed.  Those are not the same thing.

Fortunately after some searching I found some solutions.  Some have coded fixes for this and sell the software for around $20 to $30.  I don’t particularly like the idea of paying to fix something that shouldn’t be broken in the first place so I found another way.  I have several Logitech mice sitting around the house.  I have one that is a three-button, scroll wheel mouse that’s relatively new.  It was the mouse I used on my old system before the Mac. I downloaded and installed the Logitech Control Center for the Mac and hooked up the Logitech three-button mouse to my Mac.  I set the acceleration curve to 1 and then assigned the left and right buttons, along with the scroll wheel and the scroll wheel button to their Mighty Mouse counterparts.  This mouse has a third button.  On my Mighty Mouse I had the two side-squeeze buttons set to run Expose.  I was able to map my third button on the mouse to Expose, completely replacing the functionality of the Mighty Mouse with the Logitech mouse.  Now the acceleration curve is fixed and my Mac feels like a real computer again.

I’ve read that you can also buy a Microsoft Intellimouse and install the accompanying drivers.  This apparently fixes the problem too.  As I said there are third-party solutions like Steer Mouse as well.

So I didn’t find a free solution but I was able to utilize an existing investment without having to spend any additional cash.  It’s frustrating that this even had to happen.  Apparently the acceleration curve has a different effect on the mouse pointers of the Mac Books.  It seems to be the iMac that suffers primarily from this.  I could live with that if Apple would provide a way to adjust the curve.  I can only hope that it’ll make it into the next release.  Of course it took them forever to wake up and realize that the right click button on the mouse was important and they finally included it, however begrudgingly.  Sometimes they can be hard-headed.

I hope this might help someone who is having this same problem.  If you’ve already got a Logitech mouse lying around the Control Center software is a free download.  You might also have an Intellimouse with which you could do the same thing.  Both of those mice are pretty cheap so if you do have to buy one it won’t break the bank.