Maybe the next phase of Apple could return to flowing shapes and save our wrists.
If your wrist is in contact with the edge of the laptop while you are actively typing, then your typing style has a good chance of giving you RSI. You'd be better off trying to fix that than trying to make the fast path to RSI more convenient.
In my first job - i think it was in 1997, I had my own small room with an L-shaped desk with a rounded corner. That gave a few inches of space for resting my arms - both when typing on a quite reasonable Pentium laptop, and especially when using the mouse.
Since then, the desks and the chairs has become shittier and shittier. Except perhaps when a was a consultant for an HR-department.
The U-shaped desk was probably the best ergonomically designed workplace I've had. Maybe a wheat-filled pad along the desk would have made it better.
If your arms are resting, then your fingers and wrists are doing the maximum amount of reaching as you type. If you use a wrist rest you are encouraging your fingers/wrist to reach up (bend in your wrist) instead of neutral or reaching down (more natural position).
Why ?
If you were taught piano by any teacher worth their fee, then your position is natural, effortless and your wrists are limp without tension.
Exactly the same position as an ideal computer keyboard position.
Piano position is the best keyboard position. Your fingers are doing the work.
If your wrists are not straight while typing a lot, that's really bad. I constantly see people typing with their wrists either significantly flexed or significantly extended; doing that a lot is a fast road to RSI, and even doing it a little is pretty unpleasant and inadvisable.
If you are going to type a whole lot at a stretch (say, as a programmer or writer), you want your arms to be mostly passively supported from the shoulder. Having your arm bent at the elbow doesn't cause much strain, as long as the upper arm is hanging loosely down with your shoulder relaxed – so bring the keyboard relatively close to your torso. Resting your wrists, palms, or forearms on some surface and then typing generally causes more strain than having your wrists and palms "floating" above the keyboard while actively typing. You can rest the fingertips lightly on the key tops if you want. You can rest your palms on a palmrest or arms on an armrest (or table, or lap, or whatever) while you are taking a break from typing. It's generally a good idea to take regular breaks.
If you get RSI playing the piano then you had a shit piano teacher.
My palms are hovering over or resting on the chassis, and I sit high enough that my wrists do not come in contact with the edge of the case or desk. The majority of the weight of my arms is supported by my shoulders. For me, the ideal height happens to be pretty close to a neutral wrist position.
It is a solved problem.
The solution is PBCAK (Problem Between Chair And Keyboard).
When people learn the piano, they learn correct position. And a good piano teacher will not allow the student to get away with bad habits.
But if people come to the computer keyboard without the piano, they have no teacher watching them like a hawk.
They then develop bad habits and those bad habits are allowed stay with them the rest of their life.
Then those people bitch and moan about RSI becuase they are typing with the most ludicrous wrist positions.
Sometimes I think it comes down to actual typing technique. For example. I've heard of "Emacs pinky" which is easily avoided by simply using the Ctrl key opposite the key being pressed (use right Ctrl for C-c for example). I religiously never use Ctrl, Shift or Alt + another key with the same hand and I feel that's been huge. Also my elbow, wrist and hand always form a straight line to the keyboard with a standard laptop keyboard and the right body position/desk and chair adjustment.
The screen on my Macbook Air has been the exception. I wonder why they can't just use the same display on those that they do iPad. Seems better quality, as well
Note: Left hand wrist areas are currently out of stock.