
Spinward Marcher |
Why wouldn't they?
Because it states somewhere that bonuses don't usually stack.
And i cant tell because although they are very well explained and ambiguities are well dealt with the rules are laid out with no section on mechanics - you have to glean mechanics from everything else which is really tricky.
Rynjin |

Bonuses of the same TYPE don't usually stack (and untyped bonuses from the same SOURCE do not).
A class skill's +3 is an untyped bonus, and Skill Focus comes from a different source, so they stack.
"Bonuses are numerical values that are added to checks and statistical scores. Most bonuses have a type, and as a general rule, bonuses of the same type are not cumulative (do not “stack”)—only the greater bonus granted applies.
The important aspect of bonus types is that two bonuses of the same type don't generally stack. With the exception of dodge bonuses, most circumstance bonuses, and racial bonuses, only the better bonus of a given type works. Bonuses without a type always stack, unless they are from the same source."
From the glossary of terms, under "Bonus" found here for future reference.