Even if it does shrink significantly more in one direction than the other (which seems unlikely to me), I don't see how that would make any difference in your covering job.

Suppose you are covering a square. Why would it matter which way shrunk more? Now suppose it's a rectangle? Why is it better to be tighter one way than the other? Loose is loose, no?

Please explain. I just finished a wing in which I ran the alleged grain chordwise on the wing. It worked great. Did I do the right thing, or was I just lucky?