DC robe bonus is insane too, the weight limit O.O it's like 20% extra, not to mention crazy good pdef...its definitely noticeable.
If you don't have the full set, no you don't get the bonus...it is worth the difficulty.
also, a dc robe to +6 is only risking it twice...a full piece armor can be safely enchanted to 4...it's by far the easiest part...boot's and gloves can be done by brute force because the market prices are reasonably low, but goodluck on helms >.>
I've blown more armor pieces going +4 than +5. Of course that's only because I've blown them going +4. I guess I'm just unlucky. At least most were D and C grade.
The +6 Bonus's are great IMO. What sucks is that Armor Enchants do not keep the same % chances each time you click them.
Where is this documented? I thought they were the same as weapons, same % of failure each time applied...
Well the documentation does say armor has a 66% chance of success every time just like weapons but no one who has OEed a lot (that I know at least) believes it. lol
I am not sure about keeping the same percent each time, my experience has been +4->+5 is very hard while +3->+4 is easy. The problem with all these theories on OE is that usually more importance is placed on each data point than it deserves. I have not done enough armor OE and have not kept good enough records to have any statistically useful data.