(It's good to know that other people have this problem, too.)
So, it sounds like the thing to do for cloudiness (which apparently results in drag) is the following:
1. Polish with a microfiber cloth. (Some suggest a jeweler's cloth-- usually for cleaning sterling silver jewelry.) If that's not enough...
2. Polish with vinegar on a soft cloth. (Someone else suggests a damp cloth and baking soda or toothpaste and a cotton cloth.) If that's not enough...
3. Clean/polish with something stronger. (WD40? Specially formulated tarnish remover for nickel-plating-- or possibly chrome?)
Sounds like those methods may work for some people, but not for others-- and once the plating has completely worn through in spots, there's not much you can do, short of re-plating them, which isn't really an option.
I've read that cleaning the needles with alcohol can prevent or delay tarnishing, but honestly, I'm unlikely to clean my needles after every use. That's just too much of a hassle and would end up discouraging me from picking up and knitting a few rows/rounds in between other tasks.
If the nickel has gone beyond "clouding" and actually begun to chip off, that indicates that there's a problem with the needles themselves, and if they are under warranty, you can have them exchanged. (My needles don't have that sort of warranty, I'm pretty sure!)
If the plating has come off subtly, though-- not in chips-- I'd probably assume it has something to do with my personal chemistry more than the quality of the needles themselves.
- - - - - - -
In any case, I'm still determined to never buy another nickel-plated tool (beyond cheap embroidery needles). Donald encouraged me to go ahead and order some of the stainless steel needles to try, so I did. They should arrive sometime between Friday and the following Wednesday. (Exciting!)
I took the opportunity to also try the sharper "lace-tip" needles.
There are conflicting reports about how good the sharper points are.
--The sharp points make it easier to get the needle into multiple stitches (as you frequently have to do in lace knitting).
--If they're very sharp, and if you're a "tapper" (i.e. someone who pushes the left-hand needle back into the unworked stitches with your right pointer finger)-- which I sometimes am, unless I resist the urge-- you can actually get sores or break the skin.
--Some knitters say that the longer points are less ergonomic for plain knitting/purling.
--If you work close to the tip, you may find your work "tightening up" on you-- the result of working the stitch on the tapered tip instead of on the shaft of the needle.
Looks like more cons than pros (g), but I may have missed some pros-- and anyway, I still want to try them. (I remember in one of my most-recent lacy projects, I had a lot of trouble getting the needle where it needed to go, in some stitches. That kind of thing decreases your speed and enjoyment.)
I ordered a ChiaoGoo 47" Red Lace stainless steel circular in size 6, a 40" Hiya Hiya Sharps stainless steel circular in size 8, and a 40" Hiya Hiya (not sharp) stainless steel circular in size 10. (So two lace-tip/sharp needles and one standard, all stainless steel.)
The stainless steel is reported as being less slick than the nickel, so I'm curious to give them a test drive. I think I prefer slick metal, but if nickel doesn't last for me, that's not an option. As for the aluminum Boye set, as long as really sharp points aren't required, I'm pretty happy with them. (And I'll keep this in mind for the future, if the stainless steel doesn't work out: Making Boyes Better. The only downside to that elegant solution is that, if you want to glue the adapters into place, which seems like the way to go, you need a pair for each needle size. It's a lot cheaper than buying an entirely new set of needles, but still adds up-- and then you have to hope that the glued-in adapters stay glued.)
Choosing which sizes to get in which sharpness is the kind of thing I could easily spend days agonizing over, but in the end I had to admit that there's no way to know which combination is going to be best for me, so I made an educated guess.
Since most of what I knit doesn't have to hit a very specific gauge, I decided to space out the sizes over the range that I seem to use most (and is most frequently represented in my Ravelry queue). Chances are that if a pattern calls for size 7, a size 8 or 6 will work in a pinch. (Or I can use the interchangeables I already have.)
With any luck, I'll love at least one of these needles and can fill in any gaps in my collection over time.