I must say that I always thought (don't know where I learned it) that the
corrugations were there to ease flattening of the sole.  I can certainly say
that I've never noticed any difference in ease of use but, then again, I
have been accused by SWMBO of not being the most "observant" guy!

Mickey

Ed asks: 

So - do the corrugations really do anything for function?  Does it depend on
the size of the plane, the species of wood, or the relative humidity?  

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