It's a fair question and I can understand why you would be skeptical.
The blush is caused by moisture infiltrating the finish. An oily substance
displaces the moisture and thus, the blush.
I have used the petroleum jelly trick for some time and had heard about the
use of peanut butter but was also skeptical about it's use.
What got me to try it (peanut butter) was a trivia question my wife found in
a (I think it was) Readers Digest. The question was, "Why does peanut butter
stick to the roof or your mouth?'. The answer was, "Because it draws the
moisture from the roof of the mouth making it dry enough for the peanut
butter to stick"
These aren't instant cures and it may take a day or two, but it does work.
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