hey jonah,
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But for the life of me, I have never gotten any response to the topic, "As your angle changes from 45,45,90 what happens to the resistance of forces"
Short answer: As the brace becomes more vertical it resists floor load (vertical load) more and wracking forces less.
Not sure I'd agree with that... the load paths become different - but putting in a horizontal 3,4,5 brace will put the brace further out into the floor load path than the vertical 3,4,5 brace. And again - the load path for each load (racking vs. floor) is changed, altering the picture of how they work.
(And as an aside - I wouldn't count on a brace to resist floor loading - I'd make sure my timber is sized correctly to begin with.)
With the exception of extreme angles - both resist racking - but by taking slightly different paths.
Remember too that braces can also act as crowbars - a brace in tension with typical short stubby tenons is nearly useless - a brace in compression can pull a timber from a post if the post to beam joinery is weak or ill designed and the racking loads overwhelm the structure.
I'm a fan of altering timber heights when possible (not so easy in 'home' construction where floors like to be all on the same level) - or altering brace length. If you want to simplify things you can make 1 length for bents, 1 for walls or sections.
Typically I'll work with 2-3 sizes - larger braces up to ridges or purlins (no head knocking issues and they look silly so small tucked up in the roof system), medium sized for plates / posts (again, where window / door or head issues aren't a problem) and small(ish) on the interior / circulation where folks are always walking / using the space.
