Ok, so I'll start with what I know (or at least I think is correct).
-Damage shown on damage attributes tend to be 100% less than what is seen everywhere (on the forums, on the wiki) but that's because of the 100% base damage. IE, I see that Scrappers have a 500% damage cap, but on the Monitor window, it's capped at 400%.
-Enhancements count towards this damage cap. At say 100% damage through enhancements, I'm only 300% damage away from the cap.
So my first question is with Enhancements. I usually get my Scrapper up to 400% damage through inspirations and buffs and what have you. Does that mean, that if I have 95% damage through enhancements, once I'm at 305% damage on my Monitor window, any more +dmg is wasted?
Secondly, I know that there aren't too many +Dmg IO bonuses, but do those count towards the damage cap as well or are they separate? Theoretically speaking, if on my aforementioned Scrapper, I had +50% damage through set bonuses, would I then be able to actually go 50% above the damage cap?