How best to keep the topcase of a MacBook Pro clean to avoid aluminum splotches?

Question

On the Apple support pages it says:
MacBook, MacBook Pro, and MacBook Air
When cleaning the outside of your MacBook, MacBook Pro, or MacBook Air, first shut down your computer and unplug the power adapter. Then use a damp, soft, lint-free cloth to clean the computer's exterior. Avoid getting moisture in any openings. Do not spray liquid directly on the computer. Do not use aerosol sprays, solvents, or abrasives that might damage the finish.
To clean the screen on your MacBook, MacBook Pro, or MacBook Air, first shut down the computer and unplug the power adapter. Dampen the included cleaning cloth with just water and wipe the screen. Do not spray liquid directly onto the screen.
Important: The bottom case of the MacBook (13-inch, Late 2009) and MacBook (13-inch, Mid 2010) uses a soft nonslip material. Use a 3M Gray Microfiber or soft dye-free, lint-free cloth to clean the bottom case.
My question, though, isn't about the outside or the screen. I'm most concerned about the topcase - the area around the keyboard where your palms rest. In my experience with past MacBook Pros, after a half year or so, probably due to the erosive effect of sweat from your palms, the aluminum begins to erode and you get black splotches where the aluminum has worn away. That's what I want to avoid with my new MacBook Pro.
Is there any regular cleaning routine that anybody knows for sure prevents this from happening?
Thanks,
doug
p.s. I did not receive an "included cleaning cloth" with my new MacBook Pro retina 13". I asked about it while talking with AppleCare and they said they stopped including them with that model, but said they would mail me one.

Answer 1

PlotinusVeritas wrote:
Thats incredibly (very very rare) and only seen that kind of alloy erosion from people that nearly excrete acid from their skin
Yeah, dont sweat so much when typing   You typing in an non-air conditioned dwelling?
thats nice of em', yes theres no more little lens cleaning cloths (what they are).
Ive recommended people cut out thin lamination sheets to the exact size of the palm rests and apply them to prevent nasty acid wear.
Thats so rare, youre one of the "lucky" ones I guess
It's happened with every aluminum MacBook I've owned. I don't think there is anything unusual about my palm sweat. I don't see wet blotches after working.
With my MacBook Pro 17" (late 2006) just before the AppleCare warranty expired in 2009 I went into "former New Yorker" complaining mode until they agreed to exchange the topcase. Fortunately the trackpad was experiencing problems at the same time, so it all needed to be replaced anyway.
Afterwards I got some soft adhesive pads designed specifically for that purpose for the MBP 17". (If there is a product, there must be a market for it, so it probably wasn't ALL that rare). So I know that under the pads, which are now worn done, is probably a like-new top case.
I'm wondering if I need something like that, or whether there are daily/weekly/monthly cleaning products I can use to avoid the problem.
doug