I've now repeated that treatment morning and night letting the powder sit for ~12 hours each time for about 40 days, meaning about 80 treatments. The oil stain remains though each time I blow off the powder, a circular zone remains that I need to swipe away.
Does anyone have suggestions on other strategies? Is this number of treatments to be expected? I haven't tried anything else yet.
Answer (from @DWFII , a bespoke shoemaker): Fuller's Earth is better than talcum powder. But either way it has to be done soon after the oil hits the leather...and results depend on how heavily the leather is finished.
You might try applying a coat of rubber cement over the oil spots (try a test spot on the tongue or somewhere inconspicuous) and let it sit over night. Then take an art gum eraser or a piece of plantation crepe and gently roll/rub the rubber cement off. This should draw out and pick up a fair part of the oil but the treatment may need to be repeated.
There really is no instant or completely satisfactory solution.
This question was first posed and answered in our Official Shoe Care Thread.
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