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Wood Rafters, UBC tables

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I have some questions about the wisdom behind the design of tables for
looking
up rafter sizes in our 1994 and 1997 UBCs.

Our old code gave a lot of information on the similar tables.  Compare
with
the tables in the 1991 UBC Standard page 326-361 the new tables are lot
less informative.

Rafters are usually on slopes.  Why did the new code (since 1994)
omitted the
slope in its entries?  Isn't the reduction of live load from 20 psf to
16
psf important on the final selection?

Tables in the old code has notes to tell us the drywall and plaster
ceilings
are subjected to different deflection requirements -- the new code said
nothing.

Old code told us the low slope rafters are designed for 1/360, 1/240
limits
(plaster & drywall ceiling) and the high slope rafters are designed for
1/180 limit.  The new code just list 1/240 and 1/180 and no mention
about
how to apply them.

Am I the only person that find the old tables (pre-94 UBC) are a lot
more
useful?  Or are you all converted to light gage steel studs and don't
give
a thought about these tables anymore?


Sam Chang, SE
Cupertino CA