Metalguy,
I'm sure submerging the razor in alcohol accelerated the corrosion because of the water in the alcohol. Instead of just atmospheric moisture being in contact with the metal, now a lot of water was in contact. Leaving the blade in the handle could have also promoted corrosion if the dissimilar metals created a battery.
They say WD40 displaces water, but I wouldn't want to get it into any cuts. I think any oil should be washed off before use, but baby oil would be the safest.
Dik,
I like the idea of using a small battery to provide some cathodic protection. I don't imagine it would be too hard to rig up a battery, anode, and a couple of steel alligator clips. Don't use copper clips and if copper wire is used, seal it up well with silicone glue. I'd add an adjustable resistance too because a 1.5 V battery could supply way more current than was needed (depending on the electrolyte.)
IFRs,
Imersion in a liquid is fine, but it would have to be baby oil. The idea is to use a liquid that won't absorb water from the air and will prevent water vapor or liquid from touching the blades. The oil would also seal the blades from oxygen. Oxygen and water together cause corrosion to occur easily. Alcohol or soap would not give this protection. Complete immersion wouldn't be necessary, just an unbroken coating of oil on the blade edge.