You will get 10 different stories probably, but keep this in mind...

You want some shrinkage initially....

The shrinking pulls everything together and gives the wing rigidity (i couldnt belive the diffence on my first build, i could flex the wing 20ish or so degress twisting it before i covered it, and none at all after it was covered)

Thats why alot of wings are built so light these days...you couldnt do that with fabric or anything other than the covering we use today..