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gang nail wood truss design

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After reading some of the responses to the design of the wood trusses by WTCA,
I have one additional question.  The UBC horizontal diaphragm table (23-I-J-1)
is based upon the framing members being Douglas Fir or Southern Pine only.
Per footnote 2, use of any other species requires the shear values to be
modified (0.82 and 0.65 factors).  

Typically when I have seen calcs for the trusses, they are using SPF or some
other wood species, even when the general notes say to use Douglas Fir only
for the the top cord because of nailing requirements to comply with the UBC
Diaphragm table.  I don't know what the factor of safety is associated with
the UBC diaphragm table, but  I don't want to recalculate the diaphragm shears
because the truss manufacturer wants to use a wood species other than Douglas
Fir or Southern Pine.  

Has anyone else run into this problem (it applies to Standard Structures wood
truss purlins also) or been concerned about it.   It seems to me that for
small residential construction it may not be a problem, but on larger
commercial projects there can be a problem, especially if you are bracing
concrete block walls and have high shear forces. 

Michael Cochran