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Completly shearing a building (also answer to perforated shearwalls)

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There is a design example in the 1998 Wood Seminar notes published by SEAOSC 
and authored by Bill Nelson and Doug Thompson. This is a very complete design 
example.
This poses another question that plaques me.

As I traveled from California to Illinois (Chicago) I noticed many different 
types of structures. When sheathing (plwd or OSB) was used, it was generally 
used on the entire structure at each level or (in the Midwest) at the lowest 
level only. 

It seems that California contractors and designers account for every linear 
foot of sheathing applied to a residential structure (they are much more 
liberal with sheathing on commercial and industrial structures) - generally 
accusing the EOR of overdesigning if more than the minimum sheathing is 
applied to a structure.
This makes compliance to the latest code fairly easy as it is a simple thing 
to disregard openings and design each panel for deflection and uplift.

Now that we designed this complicated structure with the minimum sheathing 
required by flexible and rigid analysis, the contractor decides to sheath the 
entire house and does so with the same thickness of sheathing as the 
shearwalls, but reduced the nailing to the minimum unblocked capacity allowed 
by code (say 8d @ 6:12 for sake of argument). 
Theoretically, only the designated shearwalls will initially absorb shear 
until they reach a point of deflection that equals or exceeds the stiffness 
of the rest of the wall segments which are of various width and heights (due 
to windows and doors). 
The contractor has, essentially, changed the balance of distribution of shear 
through the diaphragm based on the relative stiffness of walls in each line 
of shear.

Is the EOR expected to go back to the design board and rebalance the shear 
based on revised stiffness or accept the original design as minimum 
compliance and disregard the potential for damage caused by the additional 
sheathing? Who is expected to pay for, what is perceived to be the contractor 
or designers good intention to improve the performance of the building? 

Dennis S. Wish PE