Disaster Area --
In the early 1900s USP Mineral Oil was often used as a lubricant for fine, light-duty use. Although not as good a lubricant as correctly-refined sperm whale or porpoise-jaw oils, the mineral oil was less expensive and didn't stink to high heaven.
Today, USP Mineral Oil is as good a lubricant as it ever was, and it's not toxic so it's safe (although I don't know if it's USDA approved) to use as a whetstone lubricant when sharpening knives used to prepare food.
On the other hand, USP Mineral Oil has never been a superior lubricant; it does not contain any anti-wear or corrosion-inhibiting additives found in today's better lube oils.
Most PM Regulars seem to have a soft spot in their hearts for Mobil oils . . . we just plain like Velocite, DTE, and Vactra . . . but equivalent oils from any of the major oil companies work better as general-purpose lube oils than does USP Mineral Oil. The drawback to these oils is simply that they're packaged in big packages (think 5 gallon pails, only sometimes in 1 gallon jugs) and stocked only by petroleum distributors (although many "professional" auto parts stores can get them).
But there IS good news. Most grocery stores, gas stations, auto parts stores, and discount stores sell Automatic Transmission Fluid (ATF) in 1 quart bottles for a couple of bucks. Any ATF meeting General Motors' Dexron II, Dexron III, or Dexron higher-number specification makes a good general-purpose lube oil that will serve most needs at least as well as Starrett's Tool & Instrument Oil.
The only two downsides to using Dexron ATF in this way that I'm aware of are 1) ATF is NOT "food safe", and 2) ATF contains dye that will stain any lighter-colored thing it sinks into.
John