[Typhus]

Both the Awareness Biosense (Tactical) and the Attention Co-Processor can add to Defense tests.  Does the +4 Enhancement maximum idea preclude getting both at the max rating for a total of +6 Defense? 

Co-Processor: "Each rating of an attention co-processor grants +1 die for Defense tests"
Awareness: "Gain a +1 dice pool bonus per rating on any defensive tests."

I thought the enhancement bonus maximum applied to attributes only, and Defense is not an attribute (derived or otherwise) that I can tell.  Is "Defense" in this context a holdover from 5e, and thus an errata issue for the Attention Co-Processor?  If so, should it match the Awareness Biosense rule language instead ("+1 defensive tests") or do something else?

[Xenon]

I'd assume that there is no cap on defense tests (as you say, they are not attributes or skills). That it stack with dice you get from the Cover I, II, III, IV status effect, the Prone status effect, Block minor action, Dodge minor action, Full Defense action, etc. all stack (with no cap).

"Defense test" seem to be the key phrase used in SR6.
Having said that, "Defensive tests" is for some reason also used for the Combat Sense adept power :-(
(note that spell with the identical name seem to instead increase the Defense Rating, is this intended?)

I guess for consistency I, both Combat Sense adept power and Awareness should probably change from "defensive tests" to "defense tests" (either that or spells, status effects and actions should all change from "defense test" to "defensive tests").

[Hobbes]

FWIW Missions caps calculated tests like Drain, Soak, Defense, and so on.  So you could get a +4 to each Attribute used in the test, and then another +4 to the test itself.  Things with an Action cost, Dodge, Full Defense, and the like, are not capped.

But RAW I can't point you to a rule that calls out a cap for these kinds of tests, so very arguably there isn't one.

[MercilessMing]

There's no cap to dice pool bonuses, and no limit to the number of dp bonuses that can be applied.

[Xenon]

In SR6 almost all stacking modifiers were converted into status effects, AR and DR bonuses or various edge triggers...

...which I wonder if not some of the "new" +Defense Test Dice Bonuses should perhaps have been better off as +Defense Rating Bonuses instead ;-)

[Typhus]

Are there any general guidelines on when things should be categorized a certain way in regards to bonuses?

So for example, you mentioned that progressive DPMs are now status effects.  What would differentiate the Defense Bonus vs bonus defense dice?  In my mind at the moment, Defense bonus would come from something that is worn and can soak some damage (in theory), but defense dice are more agility/awareness based.  That much makes sense in my head, but I don't know off top if the published stats support that consistently.

[MercilessMing]

In SR6 almost all stacking modifiers were converted into status effects, AR and DR bonuses or various edge triggers...

...which I wonder if not some of the "new" +Defense Test Dice Bonuses should perhaps have been better off as +Defense Rating Bonuses instead ;-)

H&S Threat Analysis definitely needs nerfing, if you're looking for one then start there!

[MercilessMing]

Are there any general guidelines on when things should be categorized a certain way in regards to bonuses?

So for example, you mentioned that progressive DPMs are now status effects.  What would differentiate the Defense Bonus vs bonus defense dice?  In my mind at the moment, Defense bonus would come from something that is worn and can soak some damage (in theory), but defense dice are more agility/awareness based.  That much makes sense in my head, but I don't know off top if the published stats support that consistently.

They don't.  In the core rulebook, it's mostly consistent that way, other than (off the top of my head) Cover, which gives both +dice and +DR.

Firing Squad made small unit tactics buffs/debuffs affect DR
Charismatic Defense ("too pretty to hit") quality makes CHA replace BOD in DR.
etc

[Xenon]

And then you have Combat Sense spell that give DR and Combat Sense adept power that give dice...... :-/